US3127773A - Sampling - Google Patents

Description

Ap 7, 1964 c. M. BLUMENFELD SAMPLING 2 Sheets-Sheet 1 Filed April 17, 1961 INVENTOR. CHARLES M BLUMENFELD BYMMHZ-Z ATTORNEYS April 7, 1964 c. M. BLUMENFELD 3,127,773

SAMPLING Filed April 17, 1961 2 Sheets-Sheet 2 IN VEN TOR. CHARLES M BLUMENFELD ATTORNEYS United States Patent ()1 3,127,773 SAMPLING Charles M. Blumenfeld, 470i) Parlrridge Road, Sacramento, Calif. Filed Apr. 17, 1961, Ser. No. 103,477 6 Claims. ((131. 73-423) This invention provides an improved automatic sampler.

The sampling device of this invention may be used in a wide variety of applications, but it is especially useful with the type of automatic analyzer sold under the tradename Auto Analyzer by Technicon Instruments Corp. of Chauncey, New York.

In presently available sampling devices, such as the Auto Analyzer, a suction tube is swung through an are into and out of an open sample container which holds a liquid sample to be analyzed. Due to the arcuate path traveled by the sampling tube, the sample container must be relatively short with respect to its diameter. Such containers are not normally of the size in which the liquid sample is originally collected. Consequently, samples are transferred from an original collection chamber into the sample containers used with the Auto Analyzer. This procedure has several disadvantages. It requires a supply of sample containers other than those in which the liquid sample is originally taken. Such sample containers are usually small and therefore cannot be marked easily for identification. Moreover, in transferring samples from one container to another there is often the possibility for a contamination or confusion of the samples.

This invention provides an improved automatic sampling device for removing liquid samples from the original container in which the sample is collected. This has the advantage of eliminating the previously required special size small containers, and also reduces the possibility of contamination or confusion because the samples are kept in the original containers, which are usually relatively large and easily labeled.

Briefly, this invention contemplates an automatic sampler which includes a rotatable rack and a plurality of elongated open sample containers mounted on the rack. Means are provided for rotating the rack to move the containers past a sampling station. An elongated suction tube is mounted to extend toward a sample container at the sampling station, the tube being disposed to be substantially parallel to the longitudinal axis of the container. Means are also provided for moving the tube longitudinally into the container to remove a portion of the sample.

Preferably, means are provided for rotating the rack intermittently so a sample container at the sampling station is held stationary while the tube is moved into and out of it. The portion of the tube entering the sample container is relatively rigid, and is connected to a flexible hose for removal of the sample by suction. Means are also provided for adjusting the position of the container longitudinally with respect to the rack so that for a fixed travel of the sampling tube, a sample portion can be taken from different levels of the sample container. Means are also provided for indicating on the rack the relative position of the tube when it moves into the sample taking position in a sample container.

In using the invention with currently available automatic sampling apparatus in which a suction tube is rocked along an arcuate path into and out of a sample container, means are provided for attaching the rack to the conventional equipment and converting the rocking motion of the conventional prior art dip tube to a rectilinear motion for the sampling tube for this invention. Preferably, this is achieved by connecting the tube to slide along an elongated guide rod disposed parallel to the longi- "ice tudinal axis of a sample container at the sampling statron.

These and other aspects of the invention will be more fully understood from the following detailed description and the accompanying drawings in which:

FIG. 1 is a plan View of the presently preferred embodiment of the invention;

FIG. 2 is a view taken on line 22 of FIG. 1;

FIG. 3 is a view taken on line 33 of FIG. 2; and

FIG. 4 is a fragmentary elevation, partly broken away of an alternate means for holding a sample container in the rack.

Referring to the drawings, a box 10 includes a horizontal bottom 12, four side walls 14, and a horizontal top 16. An electric motor 18 is mounted on the bottom of the box and includes an upwardly extending vertical power shaft 20 attached to a horizontal drive gear 22.

A pinion gear 24 is mounted to rotate on a vertical stub shaft 26 secured to the top of the motor. Gear 24- engages the drive gear 22. A rocking cam 28 with a lobe 29 is formed integrally with the pinion gear 24 and rotates with it. A rotatable cam follower wheel 30 is mounted between the ends of a horizontal cam arm 32 to rotate about a vertical pin 33 and ride against the outside surface of the roclc'ng cam 23. One end of the horizontal cam arm is secured by a vertical pivot pin 34 to a block 36 secured to one of the side walls of the box. The rocking cam lobe 29 oscillates the cam arm as the cam 28 rotates.

A wire link 38 is connected at one end to the free end of the horizontal cam arm, and at its other end to the lower end of an upright vertical rocker post ll which extends up through an elongated diagonal slot 42 in one corner of the top of the box and is secured adjacent its upper end by a horizontal pivot pin 44 to a block 46 mounted on the box top adjacent the slotv A curved dip tube 4 8 is rigidly secured to the upper end of the rocker post 4% so that the dip tube moves between the solid and phantom line positions shown in FIG. 2 as the motor shaft 26 rotates.

One end of a lower bar Si? is rigidly held by a clamp 52 to the curved dip tube 48. The other end of the lower bar is secured by a horizontal pivot pin '3 to the lower end of an upper bar 54, which is attached at its upper end by a horizontal pivot pin 56 to one end of a rocker arm 57 secured intermediate its ends by a horizontal pivot pin 5-3 to the upright portion of a C-shaped frame 69. The end of the rociter arm remote from the upper bar is divided into two horizontally spaced branches 62 (see FIG. 1). Each branch includes a longitudinal groove 64 opening out of its end to receive a transverse drive pin 66 extending outwardly from each side of an elongated traveling block 6% disposed between branches 62, and arranged 'to slide up and down on a vertical guide rod 69 secured at its ends across the open portion of the C-shaped frame. The drive pin 66 is free to slide back and forth in the groove 64 as the rocker annl 57 is moved up and down by the linkage connecting it to the curved dip tube 48, which is oscillated between the solid and dotted line position as described below. The movement of the rocker arm 57 up and down causes the traveling block 63 to slide up and down on the guide rod 69. The right (as viewed in FIG. 2) end of the traveling block includes a vertical bore 76 through which is press-titted a sampling tube 72. The lower end of the tube rnalces a sliding fit down through a relatively large vertical guide bore 74 in one end of a horizontal guide bracket 76 rigidly attached at its other end to the upper portion of a vertical support rigidly secured at its lower end by a bracket 8%) to a side wall of the box. As shown best in FIGS. 1 and 2, the upper end of the support 7% includes an outwardly extending dog leg -82 which is 3 rigidly secured to the, intermediate portion of the C- shaped frame 6h. The upper end of the sampling tube 72 is connected by a flexible hose 84 to conventional analyzing apparatus such as the Auto Analyzer.

Returning to the drive gear 22 turned by the motor in the box, a pinion gear 90 is mounted to rotate on a vertical stub shaft 92 secured to the top of the motor. The gear 99 engages the drive gear 2 2, and includes on its upper surface an integrally formed turning cam 94 which has a lobe 96 that drives a cam follower 98 and an elongated paw-l 1% supported to slide through a horizontal opening 1&1 in a vertical upright pawl bracket 1G2 mounted at its lower end on top of the motor. A spring 103 urges the pawl and cam follower against the turning cam S94 and also urges the end of the pawl remote from the follower wheel 538 against the teeth of a stepping gear M4 which is secured to the lower end of a vertical turn table shaft lilo journaled through a bearing 103 in the top of the box. The stepping gear is held stationary by the pawl until the pawl is moved by the lobe 96 on the cam 94. A rotatable turn table Jill) is secured to the upper end of the turn table shaft, and includes a raised annular horizontal flange 112 with a plurality of vertical sample container bores 1.14 spaced around the periphery of the flange to receive relatively short and conventional sample containers 116.

As shown best in FIGS. 1 and 2, as the motor shaft rotates, the turn table shaft is stepped intermittently by an amount required to move the sample sequentially stepped into the sampling position directly under the sampling tube, which area serves as a sampling station. While the cam follower on the pawl rides on the circular portion of the stepping cam 94, the lobe on the rocking cam causes the arcuate dipping tube 48 to dip from the solid to the dotted line position. As indicated previously, this has the disadvantage of requiring relatively short sample containers because of the arcuate path travelled by the free end (right as viewed in FIG. 2) of the curved dip tube. The arcuate movement of the dip tube is converted into vertical rectilinear movement of the sampling tube '72 as the rocker arm 57 is moved up and down by the linkage connecting it to the curved tube 48.

A rack 1 20 includes a horizontal annular bottom deck 122 to which are attached three downwardly extending vertical legs 124 spaced 120 apart. A conventional sample container 126 is rigidly secured, say by gluing, to the lower end of each leg, so the rack can easily be mounted on the turn table as shown in FIG. 2 by simply placing the three sample containers attached to the lower ends of the legs in container holes 114 in the turn table periphery.

An annular horizontal middle deck 130 is secured by vertical braces 13 2 to the top of the bottom deck, and an annular horizontal top deck 13 4 is secured by vertical braces 136 to the top of the middle deck. The peripheries of the top and middle decks contain a plurality of collinear vertical bores 13% having their cenrters located in a common cylindrical plane coaxial with the turn table shaft. A plurality of vertical clearance tabs 1138 are secured to the upper surface of the top deck, one tab being secured adjacent each respective opening 136. The tops of the tabs are in a common horizontal plane just below the lower end of the sampling tube when the tube is in its uppermost position.

A separate detent block 140 is mounted on the underside of the top deck adjacent the inner portion of each bore 136. Each deten-t block has .a radial stepped bore =142, which includes a shoulder 143 at its outer end to retain a detent ball 144 urged outwardly by a compression spring 146 disposed in the bore 142 between the ball 1 43 and a plug 148 screwed into the inner end of bore 142. As shown best in FIG. 2, each detent ball bears against the side of an elongated sample container 150 disposed in vertically aligned bores 136 in the .top

4 and middle shelves. The containers 15:? are relatively long compared to their diameter, and may be of the type described in US. Patent 2,460,641 for drawing blood samples. Such containers are sufiiciently large to carry labels (not shown) to provide for identifying marks when filled with a sample.

To explain the invention, it assumed that the liquid sample to be analyzed is blood which has been centrifuged into an upper layer 152 and lower layer 154, and that a sample is to be taken from the upper layer. The technician setting the sample containers in place adjusts each container longitudinally until the interface between the layers is at the same level as the middle deck, which is just below the lower limit of travel of the lower end of the sampling tube as shown in phantom line in FIG. 2.

referably the sample is set so the interface is at least A3" below the lower limit of travel of the lower end of the sample tube to avoid contamination from the lower layer. The spring-loaded detcnt ball 144 permits the position of the sample container to be adjusted vertically, and firmly holds the container in the desired position as the rack is rotated.

The upper end of the clearance tabs 133 are just below the level of the lower end of the sampling tube when it is in its uppermost position, so the technician takes care to see that the upper end of each sample container is below the level of the clearance tabs to be sure that the containers clear the lower end of the sampling tube as the rack is rotated.

Although the legs supporting the rack can be of any suitable length, they are preferably of sufiicient length to hold the bottom shelf of the rack high enough above the turntable to provide for clearance of the curved dipping tube so that the rack can be used with presently available Auto Analyzers by simply setting the rack in the position shown in FIG. 2 and clamping the lower bar 50 to the curved dip tube. The hose 84, which is ordinarily connected to the left (as viewed in FIG. 2) end of the curved dip tube, is removed and connected to the upper end of the straight sampling tube 72. Thus, the Auto Analyzer is operated in its normal fashion, except that the arcuate rocking motion of the curved dip tube is converted by the above described linkage to rectilinear motion so that the straight sampling tube is moved longitudinally into and out of the large elongated sample containers as they are moved sequentially past the sampling station.

As indicated previously, the sampling device of this invention permits original sample containers to be used with presently available equipment, thereby avoiding the necessity of transferring samples from the original containers to smaller containers, which cannot conveniently be labeled, and which can become confused by technicians. Moreover, the retention of the liquid sample in its original container reduces the possibility of sample contamination.

In operation, vacuum is applied continuously to the sampling tube through the flexible hose 84 so that withdrawal of liquid sample begins when the sampling tube enters the liquid and continues until the tube is lifted clear of the liquid. Air is then sucked into the tube to clean it and separate the preceding sample from the following sample, and to drive the separated samples through conventional analytical apparatus. The operation of the analytical portion of the apparatus, such as the Auto Analyzer, is conventional, and is not described in further detail since it forms no part of this invention.

In the modification shown in FIG. 4, the spring loaded detent ball is replaced by a leaf spring 160 secured by a rivet 162 to the underside of the top deck. The leaf spring urges the sample container outwardly, and holds it firmly in the desired vertical position.

I claim:

1. In an automatic sampler having a turntable adapted to carry sample containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means connecting the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rack, means for mounting the rack on the turntable to rotate with it, a plurality of open top elongated sample container mounted on the rack, an upright guide means mounted above the rack, a block mounted to rectilinearly slide up and down the guide means, an elongated suction tube extending downwardly from the block, a rocker arm mounted to pivot adjacent the guide, means connecting the rocker post to the rocker arm so the arm pivots when the post does, and means connecting the block to the arm to slide the block rectilinearly up and down the guide means and move the suction tube longitudinally into and out of containers as they move under the tube.

2. In an automatic sampler having a turntable adapted to carry sample containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means connecting the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rack, means for mounting the rack on the turntable to rotate with it, a plurality of open top elongated sample containers mounted on the rack, detent means for mounting the containers on the rack to be adjustable longitudinally, an upright guide means mounted above the rack, a block mounted to rectilinearly slide up and down the guide means, an elongated suction tube extending downwardly from the block, a rocker arm mounted to pivot adjacent the guide, means connecting the rocker post to the rocker arm so the arm pivots when the post does, and means connecting the block to the arm to slide the block rectilinearly up and down the guide means and move the suction tube longitudinally into and out of containers as they move under the tube.

3. In an automatic sampler having a turntable adapted to carry sample containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means con necting the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rack, means for mounting the rack on the turntable to rotate with it, a plurality of open top elongated sample containers mounted on the rack, an elongated suction tube extending toward a sample container at a sampling station, the tube being substantially parallel to the longitudinal axis of the said container, and linkage means connecting the rocker post to the tube to convert the arcuate motion of the rocker post into rectilinear motion of the tube and move the tube longitudinally into and out of the container at the sampling station.

4. In an automatic sampler having a turntable adapted to carry sampler containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means connecing the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rack, means for mounting the rack on the turntable to rotate with it, a plurality of open top elongated sample containers mounted on the rack, an elongated suction tube having one end extending toward a sample container at a sampling station, the tube being substantially parallel to the longitudinal axis of the said container, linkage means for connecting the rocker post to the tube to convert the arcuate motion of the rocker post into rectilinear motion of the tube for moving the said end of the tube longitudinally between a first position outside the said container and a second position inside the said container, and marking means adjacent the said container to indicate the location of the said end of the tube in the second position relative to the rack.

5. In an automatic sampler having a turntable adapted to carry sampler containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means connecing the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rotatable rack, the rack including a top deck, a middle deck spaced below the top deck, and a bottom deck spaced below the middle deck, the top and middle decks having a plurality of aligned holes to receive a plurality of elongated open sample containers mounted on the rack, means for mounting the rack on the turntable to rotate with it and move the containers past a sampling station, an elongated suction tube extending toward the sample container at the sampling station, the tube being substantially parallel to the longitudinal axis of the container at the sampling station, detent means for mount ing the container on the rack to be adjustable longitudinally, and linkage means connecting the rocker post to the tube to convert the arcuate motion of the rocker post into rectilinear motion of the tube and move the tube longitudinally into and out of the container at the sampling station.

6. In an automatic sampler having a turntable adapted to carry sampler containers, a motor, means connecting the motor to the turntable to rotate it, a rocker post mounted to pivot adjacent the turntable, and means connecting the motor to the rocker post to oscillate it through an arcuate path and move a suction tube connected to the rocker post into and out of sample containers when they are on the turntable, the improvement comprising a rotatable rack, the rack including a top deck, a middle deck spaced below the top deck, and a bottom deck spaced below the middle deck, the top and middle decks having a plurality of aligned holes to receive a plurality of elongated open sample containers mounted on the rack, means for mounting the rack on the turntable to rotate with it and move the containers past a sampling station, an elongated suction tube extending toward the sample container at the sampling station, the tube being substantially parallel to the longitudinal axis of the container at the sampling station, detent means for mounting the container on the rack to be adjustable longitudinally, and linkage means connecting the rocker post to the tube to convert the arcuate motion of the rocker post into rectilinear motion of the tube and move the tube longitudinally into the container at the sampling station below the top deck and down to the vicinity of the middle deck, and back out of the container.

References Cited in the file of this patent UNITED STATES PATENTS 1,739,731 Osborne ]Dec. 17, 1929 2,270,511 Crain Jan. 20, 1942 2,604,249 Gorham July 22, 1952 3,038,340 Isreeli June 12, 1962

Claims (1)

1. IN AN AUTOMATIC SAMPLER HAVING A TURNTABLE ADAPTED TO CARRY SAMPLE CONTAINER, A MOTOR, MEANS CONNECTING THE MOTOR TO THE TURNTABLE TO ROTATE IT, A ROCKER POST MOUNTED TO PIVOT ADJACENT THE TURNTABLE, AND MEANS CONNECTING THE MOTOR TO THE ROCKER POST TO OSCILLATE IT THROUGH AN ARCUNATE PATH AND MOVE A SUCTION TUBE CONNECTED TO THE ROCKER POST INTO ANDOUT OF SAMPLE CONTAINERS WHEN THEY ARE ON THE TURNTABLE, THE IMPROVEMENT COMPRISING A RACK, MEANS FOR MOUNTING THE RACK ON THE TURNTABLE TO ROTATE WITH IT, A PLURALITY OF OPEN TOP ELONGATED SAMPLE CONTAINER MOUNTED ON THE RACK, AN UPRIGHT GUIDE MEANS MOUNTED ABOVE THE RACK, A BLOCK MOUNTED TO RECTILINEARLY SLIDE UP AND DOWN THE GUIDE MEANS, AN ELONGATED SUCTION TUBE EXTENDING DOWNWARDLY FROM THE BLOCK A ROCKER ARM MOUNTED TO PIVOT ADJACENT THE GUIDE, MEANS CONNECTING THE ROCKER POST TO THE ROCKER ARM SO THE ARM PIVOTS WHEN THE POST DOES, AND MEANS CONNECTING THE BLOCK TO THE ARM TO SLIDE THE BLOCK RECTILINEARLY UP AN DOWN THE GUIDE MEANS AND MOVE THE SUCTION TUBE LONGITUDIANALLY INTO AND OUT OF CONTAINERS AS THEY MOVE UNDER THE TUBE.

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