U.S. patent number 3,615,239 [Application Number 04/806,589] was granted by the patent office on 1971-10-26 for automated analyzer and programmer therefor.
This patent grant is currently assigned to American Hospital Supply Corporation. Invention is credited to Charles W. Chapman, Alan R. Jones.
United States Patent |
3,615,239 |
Jones , et al. |
October 26, 1971 |
AUTOMATED ANALYZER AND PROGRAMMER THEREFOR
Abstract
An apparatus especially suited for use in automated chemical
analysis wherein the operations of delivering fluids to sample
tubes and of extracting fluids from such tubes are programmed by
mechanical-electrical programming means. Such programming means
includes a plurality of rotatable elements each equipped with a
multiplicity of spring fingers. Each rotatable element corresponds
with the treatment means at a sample tube treatment station and
each of the multiple fingers is representative of a single sample
tube advanced through such treatment stations. The fingers are
adapted to sweep over contacts representative of the stopping
stations of the sample tubes and when a selected tube reaches its
particular treatment station a finger of the rotatable member
corresponding with the treatment means at that station makes
electrical contact to produce a signal which energizes such
treatment means. The apparatus also includes means for shifting the
spring fingers between operative and inoperative positions and for
synchronizing the operation of the programming means with other
components of the analyzer.
Inventors: |
Jones; Alan R. (N/A),
Chapman; Charles W. (N/A, FL) |
Assignee: |
Corporation; American Hospital
Supply (IL)
|
Family
ID: |
25194383 |
Appl.
No.: |
04/806,589 |
Filed: |
March 12, 1969 |
Current U.S.
Class: |
422/65; 141/130;
200/38R; 422/67 |
Current CPC
Class: |
G01N
35/021 (20130101); G01N 35/1065 (20130101) |
Current International
Class: |
G01N
35/02 (20060101); G01N 35/10 (20060101); B01L
009/06 (); B01L 011/00 (); G01N 001/10 () |
Field of
Search: |
;23/259,253,23A
;141/130 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wolk; Morris O.
Assistant Examiner: Serwin; R. E.
Claims
We claim:
1. In combination, transport means for conveying a sample from a
loading station to a treatment station, treatment means for
treating a sample at said treatment station upon receiving an
electrical signal, and a programmer comprising a member mounted on
a rotatable shaft and provided with at least one radially extending
finger, a contact member having a surface normal to said shaft and
adapted to be engaged by said finger, said finger being movable
along said surface upon rotation of said shaft from a first
position corresponding with the introduction of a sample at said
loading station to a second position corresponding with the arrival
of said sample at said treatment station, electrical contact means
on said surface engageable by said finger at said second position
for producing an electrical signal upon contact by said finger,
means for transmitting said signal to said treatment means, and
driving means for driving said transport means and said shaft in
timed relation so that the interval for conveying said sample from
said loading station to said treatment station is the same as for
moving said finger from said first position to said second
position.
2. The structure of claim 1 in which said rotatable member is
provided with a plurality of said radially extending fingers, means
for normally maintaining said fingers spaced from the surface of
said contact member and out of engagement with said contact means,
and means for selectively directing any one of said fingers at said
first position into engagement with said surface when a sample is
introduced into said loading station.
3. The structure of claim 2 in which said fingers are flexible and
are formed of electrically conductive material, said fingers when
in contact with said surface being flexed and engaging said surface
under tension created by such flexure.
4. The structure of claim 2 in which said driving means operates
intermittently to drive and stop said transport means and said
shaft at regularly timed intervals, said treatment station
comprising a stopping station at which said treatment means is
located.
5. The structure of claim 2 in which there are a plurality of
additional treatment stations in spaced series with respect to said
first-mentioned treatment station, additional treatment means at
said additional stations substantially identical with said
first-mentioned treatment means but adapted to perform individually
distinctive treatment to a sample, said transport means being
adapted to convey a series of samples in succession through said
plurality of treatment stations, and a control unit comprising said
programmer and a plurality of additional and substantially
identical programmers each corresponding with one of said treatment
means and each having electrical contact means engageable by a
spring finger in said second position wherein the interval for
moving said finger of each programmer from said first position to
said second position is the same as the interval for conveying a
sample from said loading station to the treatment station of the
treatment means corresponding with each said programmer.
6. The structure of claim 5 in which said samples are fluid and are
contained in open-topped sample tubes, said treatment means
including a plurality of pumps and conduits for delivering fluid to
or extracting fluid from selected sample tubes, said driving means
operating intermittently to drive and stop said transport means and
said tubes at regularly timed intervals, said treatment stations
comprising stopping stations for said tubes where fluid is
delivered to or extracted therefrom.
7. The structure of claim 6 in which said conduits are partially
supported by a reciprocable carriage equipped with a plurality of
solenoid-actuated conduit gripping devices, each of said conduits
being extensible and retractable and being adapted to be extended
into and retracted from a sample tube at a treatment station when
the solenoid-actuated gripping device associated therewith is
energized during reciprocation of said carriage, and power means
for reciprocating said carriage in timed relation with the
intermittent drive of said transport means, whereby, a conduit is
extended into a sample tube at a treatment station only if the
solenoid gripping device therefor is energized by a signal produced
by engagement between a finger and the electrical contact means of
the programmer corresponding with such treatment station.
8. The structure of claim 6 in which said treatment means includes
a reciprocable pump carriage supporting a plurality of
electromagnets each connected to a one of said pumps, each of said
pumps being operated by reciprocation of said pump carriage only if
the particular electromagnet associated therewith is energized, and
power means for reciprocating said pump carriage in timed relation
with the intermittent drive of said transport means, whereby, a
pump is actuated to deliver fluid to or extract fluid from a sample
tube at a treatment station only if the electromagnet therefor is
energized by a signal produced by engagement between a finger and
the electrical contact means of the programmer corresponding with
such treatment station.
9. In combination, a transporter for conveying sample tubes in
succession from a loading station through a series of treatment
stations, electrically actuated treatment units for selectively
treating samples in said tubes at said treatment stations, the
sample treatment at each of said stations being different than at
the other of such stations, and programming means for automatically
actuating certain of the treatment units when a tube reaches the
appropriate treatment station in accordance with a selection made
upon introducing such tube at said loading station, said
programming means consisting of a plurality of programming devices
each corresponding with and energizing certain of said treatment
units, each programming device comprising:
a. a rotatable member having a plurality of radially extending
fingers,
b. a plate having a surface parallel with said rotatable member and
adapted to be engaged by said fingers,
c. each of said fingers being movable upon rotation of said member
between a first position upon said plate corresponding with the
introduction of a sample tube at said loading station and a
plurality of additional circumferentially spaced positions
corresponding with the arrival of the same sample tube at
subsequent treatment stations,
d. electrical contacts at each of said additional positions
engageable by said fingers for producing electrical signals for
activating the treatment means associated with said programming
device,
e. means for normally maintaining said fingers spaced from said
plate and from the electrical contacts provided thereon,
f. transfer means for selectively shifting any one of said fingers
into contact with said plate at said first position when a sample
requiring the treatment associated with said program device is
introduced into said loading station,
g. means for withdrawing a finger from contact with said plate
after said finger has traveled substantially a full revolution from
said first position,
and driving means for driving said transporter and for
simultaneously rotating all of said rotatable members of said
programming devices in timed relation with said transporter so that
the intervals for conveying any given sample tube from said loading
station to the required treatment stations are the same as for
advancing a finger of the corresponding programming device from
said first position to the respective additional contact
positions.
10. The structure of claim 9 in which said rotatable member
comprises a hub portion mounted on a shaft provided by said driving
means, said fingers being formed of flexible material and being
flexed and tensioned when in contact with said surface.
11. The structure of claim 10 in which said means for normally
maintaining said fingers spaced from said plate comprises a second
plate upon which the ends of said fingers normally ride, said
second plate being insulated from said first plate and having an
opening therein smaller in diameter than the diameter of the
fingers of said member.
12. The structure of claim 11 in which said second plate has a
recess communicating with said opening and extending radially
outwardly therefrom at a point overlying said first position of
said first-mentioned plate, whereby, a spring finger entering said
recess will be released from contact with said second plate and
will flex into contact with said first plate at said first
position.
13. The structure of claim 12 in which said transfer means
comprises a retractable panel normally extending over said recess
and preventing spring fingers riding upon said second plate from
flexing into contact with said first plate.
14. The structure of claim 13 in which a solenoid-operated lever is
connected to said panel for selectively retracting the same to
permit a spring finger engaging said panel to flex through said
recess into engagement with said first plate at said first
position.
15. The structure of claim 13 in which said first panel is provided
with a ramp adjacent said first position for returning spring
fingers which have executed substantially a full revolution in
contact with said first plate back into riding surface engagement
upon said second plate.
16. The structure of claim 9 in which said driving means operates
intermittently to drive and stop said transport means and said
rotatable members at regularly timed intervals.
17. The structure of claim 9 in which said treatment means includes
a plurality of pumps and conduits for delivering fluid to or
extracting fluid from selected sample tubes, said driving means
operating intermittently to drive and stop said transport means and
said tubes at regularly timed intervals, said treatment stations
comprising stopping stations for said tubes where fluid is
delivered to or extracted therefrom.
18. The structure of claim 17 in which said conduits are partially
supported by a reciprocable carriage equipped with a plurality of
solenoid-actuated conduit gripping members, each of said conduits
being extensible and retractable and being adapted to be extended
into and retracted from sample tubes at a treatment station when
the solenoid-actuated gripping member associated therewith is
energized during a reciprocatory stroke of said carriage, and power
means for reciprocating said carriage in timed relation with the
intermittent drive of said transporter, whereby, a conduit is
extended into a sample tube at a treatment station only if the
solenoid gripping member therefor is energized by a signal produced
by engagement between a finger and the electrical contact of the
programming device corresponding with such treatment station.
19. The structure of claim 17 in which said treatment units
comprise a reciprocable pump carriage supporting a plurality of
electromagnets each connected to one of said pumps, each of said
pumps being operated by reciprocation of said pump carriage only if
the particular electromagnet associated therewith is energized, and
power means for reciprocating said pump carriage in timed relation
with the intermittent drive of said transporter, whereby, a pump is
actuated to deliver fluid to or extract fluid from a sample tube at
a treatment station only if the electromagnet therefor is energized
by a signal produced by engagement between a finger and an
electrical contact of the programming device corresponding with
such treatment station.
Description
OTHER APPLICATIONS
Reference will be made as the specification proceeds to copending
applications Ser. No. 688,144, filed Dec. 5, 1967, now U.S. Pat.
No. 3,511,613 and Ser. No. 656,218, filed July 26, 1967, and now
abandoned.
BACKGROUND
While delivery systems for automatic chemical analysis equipment
have been known in the past, such systems have been relatively
complex in structure and operation and, partly by reason of such
complexity, have been subject to malfunctioning and, in general,
have been troublesome and expensive to maintain in operation. It
will be appreciated that any such malfunctioning may have serious
consequences since such automatic chemical analysis equipment is
intended for use in performing diagnostic tests on body fluids in
clinical laboratories.
Speed in running such diagnostic tests is also of considerable
importance because the treatment given patients may depend on the
outcome of such tests. While there are a number of different
diagnostic tests that may be run in such equipment, present
machines have a major shortcoming in their ability to perform only
a single type of diagnostic test at one time. Because of the time
and effort required to "set up" such a machine for running any
given test, it is common laboratory practice to delay the running
of a test until a substantial number of samples requiring the same
test are accumulated or, alternatively, to forego use of the
automatic equipment in favor of manual testing procedures where
there are only a limited number of samples requiring the same test
procedure. The unfortunate result may be that tests which are
urgently required for early diagnosis and treatment may either be
delayed for efficient use of the automatic analysis equipment or
may be run manually without the benefit of the high degree of
accuracy and control inherent in the operation of automatic
equipment.
SUMMARY
The apparatus of the present invention is intended for use in
automatic analysis equipment wherein a substantial number of
different diagnostic tests may be performed simultaneously. Sample
tubes containing samples of body fluids to be tested are placed in
a transporter which may be of the type disclosed in copending
application Ser. No. 688,144, filed Dec. 5, 1967, and such tubes
are advanced intermittently or incrementally through a series of
treatment stations. For any given diagnostic test there are one or
more stopping stations of the series where a selected treatment
fluid must be delivered to the sample tubes in which such test is
to be performed. Different diagnostic tests require the addition or
withdrawal of fluid from other sample tubes at other stopping
stations. Whenever the series of sample tubes is stopped, a pumping
stroke is executed by a pumping arm or carriage of the apparatus
and each tube requiring the addition or extraction of fluid at that
moment is automatically subject to such treatment.
Although the carriage executes a pumping stroke during the interval
when the series of samples tubes is stopped, actual pumping action
does not occur unless means for operatively coupling the carriage
to the selected fluid pumps has been activated. In the form of the
apparatus disclosed, such coupling means constitutes a plurality of
solenoids, one for each fluid pump. If at the time the carriage
executes its "pumping" stroke one or more of the solenoids is
energized then the pumps associated with those solenoids will
deliver (or withdraw) fluid from certain of the momentarily stopped
sample tubes. Therefore, where such apparatus is equipped with a
multiplicity of pumps, certain pumps being arranged to deliver to
withdraw fluids for certain diagnostic tests and other pumps for
other tests, each specific pump will be operated during cyclical
movement of the carriage only if the solenoid associated with that
pump is energized so that fluid is introduced or withdrawn from a
given tube of the series at the proper moment. By suitable
programming resulting in the energization of the various solenoids
at the proper moments, a multiplicity of different diagnostic tests
may be carried out simultaneously in the series of sample
tubes.
The programming means is primarily mechanical in construction and
is relatively simple in structure and operation. Because of its
relative simplicity and mechanical nature, it is found to be highly
reliable in operation, in an area where dependability is essential.
Furthermore, it is constructed in modular form, each module being
representative of a single test or operation to be performed by the
analyzer. Therefore, where the number of diagnostic tests to be
performed by the analyzer is to be increased at some later date
after installation of such a unit, it is a relatively simple matter
to add a further module for programming the analyzer to perform the
additional test.
While the programmer may have other uses, it is particularly
suitable for use in conjunction with the delivery and transport
systems of an automatic analyzer. Each module of the programmer
includes a disklike rotatable member having a plurality of radially
extending spring fingers. Such member, as well as the members of
adjacent modules, is rotated by a shaft synchronized with the
operation of a transport unit which advances sample tubes from a
loading station to a plurality of treatment stations. Adjacent to
the rotatable member of each module is a plate having a
multiplicity of electrical contacts arranged in a circumferential
series and adapted to be engaged by the spring fingers of the
rotatable member. However, such fingers are normally held out of
contact with such plate and any selected finger of the series is
allowed to make initial contact with the plate only at one point or
position where a retractable panel is located. Such panel is
retracted when a sample tube is introduced at the loading station
of the transporter and the single finger permitted by the
retraction of the panel to flex into contact with the plate
thereafter represents the newly introduced sample tube for one
complete sweep of the rotatable member. As the released finger
travels over the plate in synchronization with the movement of the
corresponding sample tube it approaches a contact element which is
representative of the treatment means at the station where
treatment of the corresponding sample tube is to be performed.
Contact between the spring finger and the contact element causes an
electrical signal to be transmitted to such treatment means with
the result that fluid is delivered to the sample tube, or is
removed from such tube, or the sample is subjected to some other
appropriate treatment at such station. The same plate may be
provided with additional contacts to be engaged in succession by
the spring finger to initiate further treatment operations on the
same sample when the sample tube arrives at subsequent treatment
stations.
If a number of samples requiring the same treatment for the same
diagnostic test are present in the transporter at the same time,
then a corresponding number of spring fingers of a single rotatable
member will be advanced over the contact plate, each finger being
representative of one of the samples and serving to actuate the
treatment means at the appropriate treatment stations when the
corresponding tube reaches such stations. However, as already
mentioned, the programmer includes a plurality of modules, each
being representative of the treatment required for a different
diagnostic test. Thus, successive tubes advanced by the transporter
may require different treatment and, in such cases, the treatment
for the respective tubes is controlled by different modules of the
programming means.
The means for delivering or withdrawing fluid from the sample tubes
comprises a plurality of extensible delivery tubes, each delivery
tube consisting of a pair of telescoping tubes formed of flexible
plastic or other flexible material. The inner tube of each
concentric tube assembly extends from a fluid pump to a treatment
station of the transporter assembly, the end of the inner tube at
the treatment station normally being maintained in position above
the sample-carrying tubes advancing intermittently therebeneath.
When fluid is to be added or withdrawn from any given sample tube,
the innermost plastic tube of a concentric pair is projected
downwardly into the sample tube prior to commencement of the
pumping stroke. It has been found that the inner tube may be
extended most effectively by shifting the outer tube to remove
slack only from the outer tube. As a result, the free end of the
inner plastic tube is extended without buckling of either tube and
dips into the preselected sample tube to deliver or withdraw fluid
therefrom. Since fluid extracted from the sample tube is withdrawn
from adjacent the bottom thereof an ample supply of fluid is
assured; conversely, since fluid delivered to the sample tube is
discharged adjacent the lower end thereof a thorough mixing of
sample and treatment fluid is achieved.
DRAWINGS
FIG. 1 is a fragmentary and partly schematic perspective view of
certain major components of an automatic analyzer, including the
programming means therefor;
FIG. 2 is a perspective view showing certain components of the
transporter, programmer, and drive means extracted from the view of
FIG. 1 for clarity of illustration;
FIG. 3 is an enlarged vertical sectional view, shown partially
diagrammatically, and taken along line 3--3 of FIG. 1;
FIG. 4 is an enlarged side elevational view of a single module of
the programmer;
FIG. 5 is a sectional view taken along line 5--5 of FIG. 4;
FIG. 6 is a sectional view taken along line 6--6 of FIG. 4;
FIG. 7 is a perspective view showing a portion of a module and
illustrating the means for transferring or diverting spring fingers
into contact with the contact plate;
FIG. 8 is a perspective view similar to FIG. 7 but illustrating the
transfer means in its normal extended position;
FIG. 9 is an enlarged sectional view taken along line 9--9 of FIG.
7;
FIG. 10 is a sectional view taken along line 10--10 of FIG. 8;
FIG. 11 is a fragmentary sectional view taken along line 11--11 of
FIG. 9;
FIG. 12 is a sectional view along line 12--12 of FIG. 10.
DESCRIPTION
Referring to FIG. 1, three basic components of an automatic
analyzer are illustrated: transporter unit A, delivery unit or
system B, and programming means C.
The transporter A is similar in construction and operation to the
unit disclosed in copending application Ser. No. 688,144, filed
Dec. 5, 1967. In brief, the transporter consists essentially of a
casing 11 having a top plate 12 defining an endless channel 13
along which a multiplicity of sample tubes or containers 14 are
advanced in single file. Each tube is slidably carried in a sleeve
15 and the sleeves are driven along the channel by a sprocket 16
carried by a shaft 17 (FIG. 2). The shaft is operatively connected
by gears 18 to a drive shaft 19 which is rotated and stopped
intermittently and at regular intervals by motor 20 and Geneva
transmission 21. Thus, the sample tubes 14 are advanced
periodically in the direction of arrow 22 from a starting point or
loading position indicated generally at 23 (FIG. 1). As the motor
20 operates, each tube is advanced into the position occupied by
the preceding tube and is then stopped for a predetermined interval
during which the operations of the delivery system B may be
performed.
It will be observed that plate 12 is disposed upon a platform or
table surface 24 and that the upstanding sample tubes 14 normally
project a slight distance above the top surface of the plate. Each
tube of the series travels no more than one complete trip or
revolution along channel 13. Tubes containing fresh samples are
inserted into the channel by an operator, or by some suitable
mechanical means, at the loading station 23 and are thereafter
intermittently advanced through one or more treatment stations
until they have made the full circuit, ride upwardly upon ramp 25,
and are finally discharged into a waste receptacle (not shown)
beneath surface 24.
Each sample tube placed into the transporter may contain a serum
sample or a sample of some other body fluid to be subjected to
automatic analytical testing. While a wide variety of tests may be
performed, in general such tests require the addition of one or
more reagents to the sample, a mixing of the reagents and the
sample fluid, a period of incubation during which the test reaction
may occur, and a final photometric analysis of the reaction
mixture. In the apparatus disclosed, five treatment stations 26-30
are indicated although a greater or smaller number may be provided
depending on the number and type of different diagnostic tests to
be performed. At each of these stations 26-30 a predetermined
quantity of a test reagent may be introduced into selected sample
tubes from a suitable source of supply, one such source for station
26 being indicated schematically at 31. Alternatively, the
treatment occurring at one or more of such treatment stations may
involve an operation other than the addition of a reagent; for
example, in one of such stations, such as station 30, a portion of
the fluid contained in each sample tube may be withdrawn and
delivered to a photometer or other testing device for analysis.
The delivery system B is most clearly illustrated in FIGS. 1 and 3
and comprises a frame 32 having upstanding side, front, and
backwalls 33, 34, and 35, respectively. The upper portion 34a of
wall 34 has a series of openings 36 through which flexible tubular
conduits 37 extend. Similarly, rear wall 35 is provided with
openings 38 which are aligned with openings 36 so that conduits or
tubes passing through such aligned openings are disposed in
parallel relation with each other.
Each conduit 37 consists of an inner tube 39 and an outer tube or
sheath 40. The inner tube 39 is in direct communication with a
source of fluid supply 31 with a pump 41 interposed along the line
for directing the flow of fluid therethrough. Tube 39 extends
through the aligned openings 36 and 38 and then curves downwardly
towards treatment station 26 and fitting 42. The fitting is in the
form of a C clamp and is held by screw 43 in any desired position
along plate member 43 which is in turn supported by posts 44 above
the top plate 12 of the transporter. The parts are constructed and
arranged so that in the normal position of tube 39 its free end 45
will be disposed directly above a sample tube 14 when such tube is
stopped at delivery station 26.
Opening 38 in rear wall 35 may be threaded to receive a fitting or
plug 46 for anchoring tube 39 against sliding movement with respect
to the rear wall. It will be observed that the stretch of tubing
between the rear and front walls is substantially straight and
extends horizontally, whereas the section of tubing 37 in front of
wall 34 is arcuate or curved and, in general, has a substantial
amount of slack. As will become apparent hereinafter, the amount of
slack depends on the proximity of the delivery unit B and
transporter A; the greater distance between such units, the less
slack is necessary.
Sheath 40 has one end secured within opening 47 of fitting 42. The
sheath curves upwardly and rearwardly, passing through opening 36
in front panel 34a (in which it is slidable), and has its rear end
48 terminating at a point between the front and rear walls of the
frame.
Directly beneath the parallel stretches of tubes extending between
the front and backwalls is a laterally extending carriage 49 which
consists in part of a horizontal bar 50 having rollers 51 at its
ends which are received in horizontal slots 52 in side walls 33.
The carriage is therefore mounted for movement between the forward
position illustrated in FIGS. 1 and 3 and the rearward position
indicated in broken lines in FIG. 3. Reciprocatory forward and
rearward motion of the conduit-extending carriage is achieved by
motor 53, crank 54, and link 55, the latter being operatively
connected to the carriage by pin 56 projecting from one end of the
carriage through slot 52 (FIG. 1).
As shown in FIG. 1, a plurality of tube gripping members 57 project
upwardly through openings in top plate 58 of the carriage. Each
cylindrical upstanding gripping member has a transverse opening 59
therethrough, such opening being in alignment with a pair of
corresponding openings 36 and 38 in the front and rear walls of the
frame. Each sheath 40 has its rear portion 48 extending through one
of such openings 59. Each opening flares outwardly at opposite ends
and even at its smallest inner diameter is substantially larger
than the outside diameter of the sheath. Consequently, when the
gripping member is in the position shown in solid lines in FIG. 2,
forward and rearward movement of the carriage will have no effect
on the position of conduit 37.
Each gripping member 57 is connected to a plunger 60 of an encased
solenoid 61 and, when such solenoid is energized, the gripping
member is pulled downwardly to grip the sheath 40 between the upper
arc of aperture 59 and the top surface of carriage plate 58. When
the rear portion of the sheath is so gripped and the reciprocable
carriage is then shifted rearwardly into the broken line position
illustrated in FIG. 3, the sheath is pulled rearwardly through the
front plate opening 36 to reduce the slack in the arcuate front
section of conduit 37 to the extent permitted by the rearward
travel of the carriage. Since the gripping member grips only the
sheath 40 and not the inner tube 39, the length of the inner tube
in front of wall 34 remains the same. However, with the slack
largely removed from the arcuate section 37, the free end 45 of the
inner tube 39 is extended or projected downwardly a distance equal
to the extent of rearward travel of the carriage. As a result, the
free end 45 of the inner tube dips downwardly into a sample tube 14
as indicated in broken lines in FIG. 3.
It has been found that the above action occurs smoothly and without
buckling of the concentric tubes. For reasons which may not be
fully understood at the present time, extension of the inner tube
is readily accomplished without buckling when the sheath is
retracted in the manner described, whereas a definite tendency
towards buckling would occur should the sheath be held stationary
and the clamping and extending forces be applied directly to the
inner tube to thrust that tube through the sheath into an extended
position.
Tube 39 and sheath 40 are both formed from flexible material,
preferably a plastic material such as polyvinyl chloride. It is to
be understood that any of a wide variety of materials having the
desired properties of flexibility, durability, and resistance to
chemical activity may be used.
Beneath carriage 49 is a second carriage 62 having sidewalls 63,
front wall 64, and rear wall 65 (FIG. 3). Rollers 66 mounted upon
the sidewalls 63 are received in horizontal channels or recesses 67
in the sidewalls of the frame and guide the lower carriage for
horizontal reciprocatory movement.
The carriage is shifted forwardly and rearwardly by a motor 68
mounted on front wall 34 (FIG. 1) and operatively connected by
shaft 69, desmodromic cams 70, riders 71, and connecting rods 72 to
the front wall 64 of the carriage.
Carriage 62 supports a plurality of electromagnet assemblies 73,
each such assembly comprising a solenoid element 74 and a core
element or plunger 75. The electromagnet assemblies are arranged in
parallel side-by-side relation with the solenoid casing of each
assembly being secured to rear wall 65 of the carriage by nut 76.
Since the assemblies are disposed in side-by-side relation, only
one such assembly is visible in the sectional view of FIG. 3;
however, it is to be understood that a plurality of identical
assemblies are concealed from view by the one illustrated. Since
the structure and operation of the multiple assemblies are the
same, only one such assembly will be described herein.
The plunger 75 of each solenoid assembly is connected by a pin 77
to the piston shaft 78 of pump assembly 41. While any suitable pump
may be used, a pump of the type disclosed in copending application
Ser. No. 656,218, filed July 26, 1967, and now abandoned, is
particularly effective and is shown in simplified form in FIG. 3.
As there shown, the pump assembly 41 comprises a housing 79
containing a pair of unidirectional valves 80 and 81. Each of the
valves consists of a sleeve of resilient stretchable material such
s rubber, the respective sleeves 80 and 81 covering valve ports 82
and 83. When piston 78 executes its intake stroke, sleeve 81 flexes
or stretches to permit the flow of fluid from the supply source 31
into piston chamber 84, and when the piston executes its discharge
stroke valve sleeve 80 similarly expands to permit the flow of
fluid from the piston chamber towards the sample tube 14 through
flexible plastic tube 39. Reverse flow through each of the
unidirectional valves is prevented because the valve sleeves fit
snugly against the ports and an increase of fluid pressure in a
reverse direction only causes such sleeves to seal more
tightly.
While motor 68 reciprocates pump carriage 62 at regularly timed
intervals corresponding with the intermittent operation of the
transport, such movement of the carriage does not necessarily
result in operation of pump assemblies 41. The solenoid plunger 75
of each electromagnet assembly is freely slidable in solenoid
casing 74 and unless the solenoid is energized movement of the
carriage and the solenoid casing mounted thereon is unaccompanied
by movement of the plunger. However, when the solenoid is
energized, then the solenoid and its plunger are locked against
independent relative movement and reciprocation of the carriage
will result in corresponding reciprocation of the plunger and the
pump piston connected thereto. Hence, each of the plural pump
assemblies 41 is operated only when the pump carriage reciprocates
and when the particular solenoid associated with that pump is
energized.
Control over the amount of fluid delivered or withdrawn through the
operation of each pump assembly 41 is achieved by microswitches 85
mounted upon carriage wall 65 adjacent each electromagnet assembly
73. The contact arm 86 of each microswitch is positioned to engage
an adjustable contact member or block 87 disposed directly above
each electromagnet assembly and in the path of movement of the
microswitch arm. The contact member is slidably carried upon a
horizontal rod 88 and an upstanding portion 89 of he member
threadedly receives a parallel threaded adjustment rod 90. The
adjustment rod is equipped with knob 91 so that upon rotation of
the knob the member 87 may be shifted between the solid and broken
line positions illustrated in FIG. 3. Engagement between the arm 86
of the microswitch and the adjustable member 87 closes the contacts
of the switch; when the arm is in the raised position illustrated
in FIG. 3 the flow of current to the solenoid is interrupted. It is
believed apparent that if adjustment member 87 is shifted into the
broken-line position so that solenoid 74 will be energized at the
commencement of a cycle of operation of the pump carriage 62, then
piston 78 will be shifted to the left to execute its full intake
and discharge strokes. However, if the contact member 87 is shifted
to the left, then the carriage 62 will move forwardly a selected
distance before the microswitch is closed and, consequently, before
the solenoid is energized and the intake stroke is commenced.
Thereafter, when the carriage executes its return stroke to pump
fluid from pump 41 into tube 39, the solenoid will be deenergized
as soon as the arm of the microswitch clears contact element 87.
Therefore, by adjusting the position of contact member 87 the
amount of fluid delivered by each pump 41 and conduit 37 to a
sample tube 14 may be easily and accurately controlled.
Primary control over energization of each solenoid 74 of a pump
assembly and each solenoid 61 of a tube extension-retraction
assembly is achieved by programming means C. Such programming means
is diagrammatically illustrated in FIG. 3 and is shown to be
connected by leads or signal lines 92 and 93 to solenoids 74 and
61. It is to be understood that the program or control means is
similarly electrically connected to the respective solenoids of the
delivery system B for each of the treatment stations 26-30 and that
the apparatus of the delivery unit B responsible for delivering (or
extracting) fluid at each of such stations constitutes treatment
means for the samples carried by the transporter.
The programmer C comprises a casing 94 having a top panel 95 and
end panels 96 connected by bolts 97. Between the end panels 96 are
a plurality of programming modules or devices 98-102, each of said
modules being substantially identical and, as shown in FIG. 1,
being arranged in spaced parallel relation. Any number of such
modules may be provided depending on the size of the analyzer and,
in particular, upon the number of different treatment procedures to
be performed thereby.
A shaft 103 extends through all of the modules and is journaled in
end plates 96. As shown most clearly in FIG. 2, shaft 103 is
operatively connected by gears 104 to drive shaft 19; therefore,
rotation of the shaft 103 is synchronized with the operation of the
transporter as well as with the operation of delivery system B.
Mounted on shaft 103 are a plurality of disks or rotatable members
105, one such member being provided for each module 98-102.
Referring to FIG. 4, it will be seen that each member 105 has a hub
portion 105a and a multiplicity of radially extending spring
fingers 105b. The number of spring fingers corresponds directly
with the number of sample tubes capable of being carried by the
transporter; therefore, while a total of 66 spring fingers are
illustrated in FIG. 4, it will be understood that a greater or
smaller number may be provided depending upon the capacity of the
transporter and the size of the analyzer as a whole.
It will be observed that the spring fingers are equally spaced and
are of equal length. As viewed in side elevation, each of the
fingers slopes away from the plane of the hub with which is it
integrally formed. The tension of the flexible fingers tends to
urge them into engagement with a contact plate or member 106 which
extends normal to the axis of shaft 103. However, such fingers are
normally held away from contact with plate 106 by a second plate
107 which is parallel with the first plate and spaced therefrom by
an insulating spacer 108. It will be observed that plate 107 has an
opening 109 concentric with rotatable member 105 but slightly
smaller than the diameter of spring fingers 105b. Consequently, in
their normal condition, such fingers ride upon plate 107 about the
edge of opening 109 and are prevented from engaging contact plate
106.
The ends of the spring fingers 105b may be bent as shown most
clearly in FIGS. 5 and 6 so that slightly rounded or curved surface
portions of the fingers engage the plates to reduce wear of the
fingers, to insure a smooth operation, and to achieve proper
electrical contact as will be described hereinafter.
Like spacer 108, contact plate 106 is formed of plastic or other
suitable electrical insulating material. However, applied to the
surface of plate 106 which faces the spring fingers is a
circumferential series of metallic contacts 110. In the
illustration given, a total of 60 such contacts are provided, each
contact representing or corresponding with a possible location of a
treatment station along transporter A. Conductive lines or stripes
of metal lead from each of the contacts 110 to a series of plug-in
connectors 112 disposed along one edge of the plate or card 106.
Thus, if module 98 shown in FIG. 4 were to control treatment
occurring at station 26 in FIGS. 1 and 3, then a suitable mating
connector 113 would be plugged into the second pair of contacts
(counting from the bottom of the plate because of clockwise
rotation of the rotatable member 105) and the signal lines 92 and
93 would lead from connector 113 to solenoids 74 and 93 as
indicated in FIG. 3.
Opening 109 in second plate 107 is generally circular in
configuration except for a recess 114 along an edge portion of the
opening. When the spring fingers 105b of the rotatable member reach
recess 114 they are no longer supported by the second plate 107
and, because of their tension, such fingers spring in a direction
towards plate 106 as soon as they reach the recess. Direct contact
between the fingers and plate 106 at that point is prevented,
however, by a ramp 115 which is secured to contact plate 106 and
which slopes away from that plate to a point above the level of
second plate 107 (FIGS. 7-10). As a result, spring fingers 105
which have advanced to the point where they are no longer supported
by plate 108 and therefore drop into recess 114 engage ramp 115 and
ride upwardly along the ramp to a point above the level of plate
107.
Between the upper end 115a of the ramp and the adjacent edge 114a
of plate 107 is a transfer opening of greater width than each of
the spring fingers 105b. Such opening is normally closed by a
retractable panel 116 which serves as a slidable trap door between
the two levels defined by the surfaces of plates 106 and 107. When
the panel is extended, as illustrated in FIGS. 8, 10 and 12, spring
fingers riding upwardly upon ramp 115 engage the panel and then
pass on to the surface of second plate 107. However, when the panel
116 is retracted, as illustrated in FIGS. 7, 9 and 11, a finger
clearing the upper end of the ramp is free to drop downwardly (by
reason of the tension in the spring finger) into engagement with
the surface of contact plate 106. A finger which has dropped
through the opening remains in contact with plate 106, and
successively engages electrical contacts 110, until it has traveled
substantially an entire revolution, at which time it again engages
ramp 115 and rides upwardly along that ramp to the opening normally
closed by the retractable panel 116. The positions of such fingers
upon the surface of plate 106 as they approach the ramp are
indicated by broken lines in FIGS. 9 and 10.
In the illustration given, the means for retracting panel 116
comprises a crank or lever 117 which is pivotally connected to
plates 106-108 by pin 118 and which has one end connected to the
retractable panel at 119 and its opposite end connected to the
plunger of a solenoid unit 120. Any suitable means may be provided
for biasing the panel into a normally closed or extended position;
in the embodiment illustrated, a compression spring 121 urges the
plunger of the solenoid in the direction indicated by arrow 122
(FIG. 8) to maintain the panel in its extended position unless the
solenoid is energized. As shown, the solenoid unit is secured to
plates 106-108 by a bracket 123.
Any of a variety of means may be utilized for selectively
energizing the solenoids of the respective programming modules.
FIG. 1 schematically illustrates a card reader 124 which may be
connected by a bundle of signal lines 125 to each of the several
solenoids and which will energize one of such solenoids when a card
125 is inserted into the reader. Alternatively, the means for
energizing the respective solenoids 120 might comprise a control
panel having a series of control buttons, one for energizing each
respective solenoid. Whatever the case, suitable means are provided
for energizing the solenoid of a program module corresponding with
a treatment procedure to be applied to a sample introduced into
loading station 23 of the transporter. Such energizing of the
solenoid will cause a spring finger to drop into engagement with
the contact plate of the selected program module and such spring
finger will thereafter advance from contact to contact in timed
relation with the movement of the corresponding sample tube from
stopping station to stopping station. When the spring finger
engages a contact 110 which is electrically connected to the
pumping and tube-extending solenoids for a given treatment station,
such solenoids will be energized and the sample at that station
will be so treated.
To illustrate the operation more specifically, it will be observed
in FIG. 1 that treatment station 26 is two stopping positions
beyond loading station 23. If a sample inserted into the transport
at the loading station is deemed to require the treatment available
at station 26, then at the time the sample is loaded the solenoid
120 for programming module 98 is energized and a spring finger
drops into a first position in engagement with contact plate 106.
The sample tube and the corresponding spring finger then advance
incrementally and in timed relation. When the finger has reached a
second position in engagement with the contact element 110 in
circuit (by means of leads 92 and 93) with the solenoids 61 and 74
of treatment station 26, the sample will be at that station ready
to receive the selected treatment. Energization of solenoid 61
coupled with reciprocation of carriage 49 causes tube 39 to project
downwardly into the sample tube, and energization of solenoid 74
results in a pumping action which supplies fluid to the sample tube
or extracts fluid therefrom. Thereafter, the conduit is withdrawn
from the sample tube and the tube along the circuit of the
transport for subsequent treatment only at those stations
programmed at the time the tube was inserted into the transporter
at the loading station.
It is believed apparent from the foregoing that the programmer may
have utility in programming operations which differ considerably
from the treatment operations disclosed herein. While an embodiment
of the invention has been disclosed in considerable detail for
purposes of illustration, it will be understood by those skilled in
the art that many of such details may be varied considerably
without departing from the spirit and scope of the invention.
* * * * *