US3768526A

US3768526A - Automatic test tube transporter and sample dispenser

Info

Publication number: US3768526A
Application number: US00126782A
Authority: US
Inventors: M Sanz; B Sturgis; C Lawson; J Bain
Original assignee: Individual
Current assignee: ICN Micromedic Systems Inc; Rohm and Haas Co
Priority date: 1970-04-03
Filing date: 1971-03-22
Publication date: 1973-10-30
Anticipated expiration: 1990-10-30
Also published as: CA950703A

Abstract

An automatically operated transporter apparatus which advances racks containing double rows of test tubes under a vertically movable aspirating and dispensing tip and tilts the tubes successively to a reference position allowing the tip to descend and engage the inner side wall of the tubes to perform its function. The tip is operationally in communication with a double pump metering and dispensing apparatus which includes a linearly adjustable eccentric mechanism which drives the pump pistons with a motion of adjustable sinusoidal amplitude. The apparatus also includes a pump valve switching mechanism which automatically switches the valves and the ports on the pumps between suction and compression strokes. The pumps may be adjusted to either work in parallel or alternating strokes. An automatic tip wiping mechanism is provided to insure precision in the processing. The apparatus can be set for continuous operation or for individual test tube processing cycle operation. Empty racks can be advanced without engaging the tip and pump apparatus. A trouble relay system gives a warning in case of any malfunction and stops the apparatus in most cases.

Description

United States Patent 1 Sanz et al.

[ AUTOMATIC TEST TUBE TRANSPORTER AND SAMPLE DISPENSER [76] inventors: Manuel C. Sanz, 50B Chemin des Verjus, Geneva, Switzerland; Byron E. Sturgis, 1806 Epworth Dr., Hunstville, Ala. 35811; Charles V. Lawson, 304 Fifth St. NE, Arab, Ala. 35016; Joe K. Bain, 2307 Rosemont St., Decatur, Ala. 3560] [22] Filed: Mar. 22, 1971 [21] Appl. No.: 126,782

[30] Foreign Application Priority Data Apr. 3, 1970 Canada 79,112

[52] 11.8. C1. 141/130, 23/230, 23/253, 23/259, 73/425.6,141/90,141/125, 141/167, 141/181, 141/168 [51] Int. Cl 1365b 43/56 [58] Field of Search 23/253, 259, 230; 356/246; 250/218, 220; 73/425.6; 141/90, 125,167, 168,181, 130

[56] References Cited UNITED STATES PATENTS 3,622,279 11/1971 Moran 141/130 Primary Examiner-Houston S. Bell, Jr. AtIomeyGerry J. Elman, Carl A. Castellan and George W. F. Simmons [57] ABSTRACT An automatically operated transporter apparatus which advances racks containing double rows of test tubes under a vertically movable aspirating and dispensing tip and tilts the tubes successively to a reference position allowing the tip to descend and engage the inner side wall of the tubes to perform its function. The tip is operationally in communication with a double pump metering and dispensing apparatus which includes a linearly adjustable eccentric mechanism which drives the pump pistons with a motion of adjustable sinusoidal amplitude. The apparatus also includes a pump valve switching mechanism which automatically switches the valves and the ports on the pumps between suction and compression strokes. The pumps may be adjusted to either work in parallel or altemating strokes. An automatic tip wiping mechanism is provided to insure precision in the processing. The apparatus can be set for continuous operation or for individual test tube processing cycle operation. Empty racks can be advanced without engaging the tip and pump apparatus. A trouble relay system gives a warning in case of any malfunction and stops the apparatus in most cases.

49 Claims, 40 Drawing Figures 'PATENTEDBUIBOHH 3.768.526

SHEET DIUF 19 MANUEL CLAUDE sn/vz BYRON EDWARD STURGES 1" I20 CHARLES I/AUGH/V LAWSON r" luv" y JOE KE/TH BA/N.

SHEET 030F 19 ZIO F/GS

3.768.526 sum user 19 I PAIENTEDQm-ao ms PATENTEUHBI 30 I973 sum D8UF 19 PAIENIEDnmao I913 SHEET 100? 19 mom 5m mom @E +5 mom n. mom

Q mmm 1 1mm mmm Qmm Na b8 2m @m PAIENTEBHN 30 ms SHEET MW 19 JNOM PAIENIEnnm 30 ms 3,768,526

' SHEET 130F 19 PATENTEUHCI 30 I915 SHEET ISUF 19 OPERATION PMFNTEHUCIBOISH I I 3,768,526

SHEET 16 F 19 MANUAL J1 SWITCH AUTOMATIC I SWITCH ADVA CE J I TIP DOWN I I J' L TIP UP TRANSPORTER TEETH J 20 TEETH l r- STNTEERVAL VALVE H PUMP TEETH L J' lllllIll lllflllll llllll ll lllllll 0.0 I.0 I5 2.0 25

IDLE GEAR R0TATI0N (DEGREESWTIME (sec) A 810 VE I MANUAL SWITCH 807 PUMP OPERATION PATENTEUHU 30 1915 3.768526 SHEET UN 19

Claims

1. An automatic apparatus for processing samples contained in a plurality of tubes mounted in a support rack comprising a base having a planar surface, at least one conduit having an aspirating and dispensing tip, means to raise and lower said tip relative to the base, means supporting said tip and the tip raising and lowering means above said planar surface, pump means of adjustable volumetric capacity in communication with said conduit means and comprising at least two pumps each having a cylinder and piston means, said pistons being constantdisplacement pistons of constant cross-section to provide accurate, positive displacement increments, stroke-adjustment means for individually varying the length of stroke of each of said pistons, motor means, eccentric means connecting said motor means to said stroke-adjustment means, said eccentric means being constructed to provide sinusoidal aspirating and dispensing pressures to said tip, rack advancement means to move a loaded support rack underneath said tip by increments so as to position each tube for lowering of said tip and cycling of said pump means, said pump means adapted to provide sinusoidal aspirating and dispensing pressures to said tip only when said tip is in the down position, and electrical means to control the operation of said motor means, pump means and said rack advancement means and to cycle said pump means and said tip means automatically upon operation of said rack-advancement means.

2. An apparatus as in claim 1 including guide means on said planar surface adapted to automatically feed said support racks to said rack advancement means, whereby a plurality of loaded racks may be automatically processed.

3. An apparatus as in claim 2 wherein said guide means comprises parallel rails on said planar surface, said rails having slot means therein, rack-pushing means between said rails and mounted for sliding movement in said slot means.

4. An apparatus as in claim 3 wherein a tensioning means is provided to put tension on said rack pushing means to bias it toward said rack advancement means.

5. An apparatus as in claim 1 including means associated with the stroke adjustment means and motor means whereby the pUmp pistons can be set to either pump in parallel or in alternately opposite directions.

6. An apparatus as in claim 1 wherein said eccentric means is linearly adjustable to set the pistons stroke from zero to a predetermined maximum.

7. An apparatus as in claim 6 including external indicator means on said apparatus to indicate the stroke setting on each eccentric mechanism.

8. An apparatus as in claim 1 wherein there are two ports in each cylinder, valve means in each pump capable of alternately placing said cylinder in communication with one port for the intake stroke and the other port during the exhaust stroke, said valve means being driven by said motor means.

9. An apparatus as in claim 8 wherein each pump is constructed so that said pistons and cylinders may be easily removed and replaced with cylinders and pistons of different constant cross section.

10. An apparatus as in claim 8 wherein at least one of said pumps has a bleed and priming means associated with its cylinder.

11. An apparatus as in claim 8 wherein each said valve means includes a rotary member and a valve switching mechanism in operative association with each said rotary member and said motor means.

12. An apparatus as in claim 11 wherein said valve switching mechanism includes a reciprocal lever means with slots therein, said rotary member having studs projecting into said slots whereby reciprocation of said lever means reciprocates said rotary valve member to shift ports between the intake and discharge strokes of said pump piston.

13. An apparatus as in claim 12 wherein said lever means is adapted to be disengaged to a position where it does not reciprocate whereby either or both pumps may intake and exhaust through only one port.

14. An apparatus as in claim 8 wherein said motor means includes motion translating means adapted to convert rotary motion into reciprocating arcuate motion and valve switching mechanisms connecting said motion translating means with said valve means.

15. An apparatus as in claim 14 wherein said valve switching mechanisms are adjustable to disengage from said motion translating means and leave either or both of said cylinders communicating with only one port during both the intake and exhaust stroke of its accompanying piston.

16. An apparatus as in claim 15 wherein said motion translating means comprises rotatable cams, vertically reciprocable members having aperture means receiving said cams and adapted to vertically reciprocate with pauses at the topmost and bottom-most positions upon rotation of said cams, pivot members on said vertically reciprocable members and adapted to arcuately reciprocate in a vertical plane upon vertical movement of said vertically reciprocal member to drive said valve switching mechanism.

17. An apparatus as in claim 16 wherein said valve switching mechanism includes pivoted levers driven by said pivot members and adapted to reciprocate in a horizontal plane.

18. An apparatus as in claim 1 wherein each of said cylinder means has two ports and a valve means adapted to switch communication of said cylinder from one port to another between the intake and discharge strokes of the piston, said ports having fittings thereon adapted to accommodate flexible conduits.

19. An aparatus as in claim 18 wherein said electrical means includes a first motion translating means adapted to translate rotary motion into sinusoidal reciprocal motion, power transmitting means connecting said motor means and said first motion translating means to provide rotation to said motion translating means, a valve switching mechanism, means operatively connecting said valve means with said valve switching mechanism, a second motion translating means adapted to translate rotational movement of said power transmitting means into substantially reciprocal movement, said second motion translating means operatively associated with said valve switching mechanism and operating it to switch the valve means between strokes of said pistons, and rEciprocating arm means connected to said pistons and said first motion translating means to provide strokes of sinusoidal amplitude to said pumps.

20. An apparatus as in claim 19 wherein said pump includes an elongated housing, said cylinder comprising chamber means within said housing, port containing means adjacent said chamber means, said port containing means including said two port bores, said valve means being a rotary member in said housing adjacent said port containing means and adapted to alternately place each port bore in open communication with said chamber means, adjustable means associated with said chamber and piston means to seal said pump against leakage, reciprocal rotating valve driving means connected to said valve means and having at least one driving stud projecting up beyond the end of said housing to engage said valve switching mechanism, said valve switching mechanism having reciprocal lever means engaging said driving stud to operate said valve means upon reciprocation thereof.

21. An apparatus as in claim 1 wherein said electrical control means includes means to advance the tube racks automatically and incrementally upon completion of each pump cycle and means to advance the racks without any processing by the tip.

22. An apparatus as in claim 1 wherein said electrical control means includes means to operate the pump means alone without advancing the tube racks.

23. An apparatus as in claim 1 wherein said control means includes means to automatically shut down the operation of the apparatus if the rack advancement means is in a jammed condition or if the tip becomes misaligned.

24. An apparatus as in claim 1 wherein said base includes means to automatically eject a tube rack which has been processed from the path of a rack commencing processing.

25. An apparatus as in claim 1 wherein said electrical control means includes means to process only one tube at a time, whereby said control means has to be manually reactivated each time to process a plurality of tubes.

26. A apparatus as in claim 1 wherein said tip raising and lowering means includes a wiper means for wiping the tip clean during the upward stroke of said tip.

27. A apparatus as in claim 26 wherein said tip raising and lowering means also includes cam and crank arm operated reciprocating means, a first slot means, slide means holding said conduit and tip and mounted for vertical sliding movement in said first slot means and flexible cord means operatively connecting said slide means with said reciprocating means to raise and lower said tip.

28. A apparatus as in claim 27 wherein wiper means comprises pivoted wiping elements adjacent the vertical path of said tip, cam means on said slide means adapted to cause the wiping elements to converge on said tip during the raising thereof and a wiping means adapted to provide separate strips of wiping paper on opposite sides of said tip path, said wiper elements adapted to engage said paper strips and push them against said tip.

29. A apparatus as in claim 28 wherein said wiping means further comprises a paper supply means, means to advance said paper strips during each cycle of said tip raising and lowering means, said reciprocating means having a cam means thereon adapted to engage said paper strip advance means and advance said paper strips a predetermined distance during each stroke thereof whereby an area of dry paper is provided for wiping said tip during each operational cycle thereof.

30. An apparatus as in claim 1 wherein each of said pump means has two ports and a valve means adapted to switch communication of said cylinders from one port to another between the intake and discharge strokes of the pistons, said ports having fittings thereon adapted to accommodate flexible conduits, said electrical means including a motor means, a first motion translating means adapted to translate rotary motion into sinusoidal reciprocal motion, power transmitting means connecting said motor means and said firsT motion translating means to provide rotation to said motion translating means, a valve switching mechanism, means operatively connecting said valve means with said valve switching mechanism, a second motion translating means adapted to translate rotational movement of said power transmitting means into substantially reciprocal movement, said second motion translating means operatively associated with said valve switching mechanism and operating it to switch the valve means between strokes of said pistons, reciprocating arm means connected to said pistons and said first motion translating means to provide strokes of sinusoidal amplitude to said pumps, and a constant force spring, one end of said spring being bent and fitting into a slot on said first motion translating means, the other end of said spring being coiled and hooked around said reciprocating arm means to elminate any looseness or play in said reciprocating arm means.

31. An apparatus for selectively or automatically processing a plurality of liquid sample containing tubes mounted in a support rack comprising a surface means, rack advance means cooperating with said surface means to advance said racks, a liquid metering and dispensing apparatus, a conduit means in communication with said metering and dispensing means and having an aspirating and dispensing tip, said apparatus adapted to provide sinusoidal aspirating and dispensing pressures to said tip only when said tip is in the down position, means adapted to raise and lower said tip into engagement with the samples contained in said tubes, rack ejection means adapted to eject processed racks from the path of a rack commencing processing, said tip raising and lowering means including a wiper means for wiping said tip as it is being raised.

32. An apparatus as in claim 31 including rack guide means adapted to successively guide a plurality of racks into engagement with said rack advance means to commence processing.

33. An apparatus as in claim 32 wherein said guide means comprises two parallel rails substantially perpendicular to the path of racks engaged by said rack advance means and being processed, and a rack push bar means mounted between said rails, a tensioning means connected to said push bar means and biasing the same to force unprocessed rack toward said rack advance means.

34. An apparatus as in claim 33 wherein said tensioning means comprises a pulley wheel mounted in one of said rails, a cord passing over said wheel with one end connected to said push bar means and the other end connected to a spring means.

35. An apparatus as in claim 31 wherein said rack advancement means includes a slot in said surface means and a rack engaging means mounted for reciprocal movement under said surface means and having a toothed means adapted to project through said slot and engage the bottom of said racks.

36. An apparatus as in claim 35 wherein said rack engaging means is mounted on a platform under said surface means, a slot in said platform underlying the slot in said surface means and generally parallel therewith, a slotted guide means mounted on the bottom side of said platform and a slide member mounted in said guide means and carrying said toothed means.

37. An apparatus as in claim 31 wherein said means for raising and lowering said tip includes a holder for adjustably holding said conduit means adjacent said tip.

38. An apparatus as in claim 31 wherein said wiper means comprises a wiper paper supply means, means providing two srips of said wiper paper on each side of said tip, means to advance said paper strips and means for pushing said strips against said tip.

39. An apparatus as in claim 38 wherein said means for pushing said paper strips against said tip comprises a pair of pivotally mounted wiper elements, said means for raising and lowering said tip includes cam means adapted to force said wiper elements against said tip as it is being raised.

40. An apparatus as in claim 31 wherein said surface means has a switch meaNs therein adapted to control the operation of said tip lowering means through said electrical control means, said electrical control means adapted to prevent the lowering of said tip when said switch means senses the absence of a tube.

41. An apparatus as in claim 31 wherein said rack ejection means comprises a pair of flipper elements adapted to shove a processed rack laterally out of the path of a rack commencing processing, and means to power said flippers.

42. An apparatus as in claim 41 including switch means in the path of said racks being processed, said switch means adapted to activate said flipper means when said rack contacts said switch.

43. Apparatus for processing a liquid to be analyzed comprising a plurality of test tubes, a rack for supporting the test tubes upright at spaced intervals along the length of the rack, a stationary table having an upwardly facing planar surface on which the rack is slidable, a flexible conduit, a downwardly extending tip at the end of the conduit having an opening or bore communicating at its upper end with the passage of the conduit and open at its lower end to allow entry or discharge of liquid through the tip into or out of the conduit, means to support the tip movably above the table comprising means to raise and lower the tip relative to the table, means for intermittently moving the rack longitudinally over the table along a path extending under the tip, positive displacement pump means comprising a piston reciprocable in a cylinder communicating with the conduit, pump driving means for intermittently moving the piston in alternate suction and forcing strokes within the cylinder, said driving means having means for interrupting the motion of the piston at the end of each stroke to provide a pause for an appreciable time before the next stroke starts, and means for coordinating operation of the several means to carry out one or more cycles, each cycle including the following steps: the rack is moved to bring one of the tubes therein to a position under the tip, the rack is stopped with the tube in that position, the tip is moved down into the tube under the tip, the piston is moved through one of its alternate strokes while the tip is in the tube, the piston is stopped for its pause, the tip is raised out of the tube, and the piston is moved through the other of its alternate strokes.

44. Apparatus in accordance with claim 43 in which the cylinder has a common port for entry and discharge of liquid with respect to the cylinder, the apparatus comprises another conduit, a member having two fixed passages, one of the passages being connected to and communicating with the first-mentioned conduit and the other passage being connected to and communicating with the other conduit, valve means for selectively connecting the common port to one of the passages for communication therewith, and the operation coordinating means including means for operating the valve means when the piston is stopped for a pause.

45. Apparatus in accordance with claim 43 comprising means for sensing a tube in position below the tip for stopping the rack-moving means.

46. Apparatus in accordance with claim 43 comprising means actuated by a rack whose tubes have advanced beyond the tip-position in the path for ejecting such rack to an area of the table to one side of the path.

47. Apparatus in accordance with claim 43 comprising means for adjusting length of piston stroke and indicating means to indicate pump stroke volume.

48. Apparatus for processing a liquid to be analyzed comprising a plurality of test tubes, a rack for supporting the test tubes upright at spaced intervals along the length of the rack, a stationary table having an upwardly facing planar surface on which the rack is slidable, flexible conduit, a downwardly extending tip at the end of the conduit having an opening or bore communicating at its upper end with the passage of the conduit and open at its lower end to allow entry or discharge of liquid through the tip inTo or out of the conduit, means to support the tip movably above the table comprising means to raise and lower the tip relative to the table, means for intermittently moving the rack longitudinally over the table along a path extending under the tip from an initial rack-entry position in the path to a final eject-position therein, means for sliding the rack laterally on the table into the initial rack-position in the aforementioned path, means for pushing the rack laterally out of the path after the last tube in the rack passes beyond the tip position, positive displacement pump means comprising a piston reciprocable in a cylinder communicating with the conduit, pump driving means for intermittently moving the piston in alternate suction and forcing strokes within the cylinder, said driving means having means for interrupting the motion of the piston at the end of each stroke to provide a pause for an appreciable time before the next stroke starts, and means for coordinating operation of the several means to carry out one or more cycles, each cycle including the following steps: the rack is moved to bring one of the tubes therein to a position under the tip, the rack is stopped with the tube in that position, the tip is moved down into the tube under the tip, the piston is moved through one of its alternate strokes while the tip is in the tube, the piston is stopped for its pause, the tip is raised out of the tube, and the piston is moved through the other of its alternate strokes.

49. Apparatus for processing a liquid to be analyzed comprising a plurality of test tubes, a rack for supporting the test tubes upright at spaced intervals along the length of the rack, a table having an upwardly facing planar surface on which the rack is slidable, said table having an entrance area, large enough to accommodate several racks, to receive one or more racks to be processed, an exit area large enough to accommodate several racks to receive one or more racks after completion of processing, and an area, contiguous to the entrance and exit areas, comprising the rack-processing path, a flexible conduit, a downwardly extending tip at the end of the conduit having an opening or bore communicating at its upper end with the passage of the conduit and open at its lower end to allow entry or discharge of liquid through the tip into or out of the conduit, means to support the tip movably above the table comprising means to raise and lower the tip relative to the table, means for intermittently moving the rack longitudinally over the table along the rack-processing path extending under the tip from an initial rack-entry position in the path to a final eject-position therein, means for sliding the rack laterally on the table into the initial rack-position in the aforementioned path, means for pushing the rack laterally out of the path after the last tube in the rack passes beyond the tip position, positive displacement pump means comprising a piston reciprocable in a cylinder communicating with the conduit, pump driving means for intermittently moving the piston in alternate suction and forcing strokes within the cylinder, said driving means having means for interrupting the motion of the piston at the end of each stroke to provide a pause for an appreciable time before the next stroke starts, and means for coordinating operation of the several means to carry out one or more cycles, each cycle including the following steps: the rack is moved to bring one of the tubes therein to a position under the tip, the rack is stopped with the tube in that position, the tip is moved down into the tube under the tip, the piston is moved through one of its alternate strokes while the tip is in the tube, the piston is stopped for its pause, the tip is raised out of the tube, and the piston is moved through the other of its alternate strokes.