US3266554A

US3266554A - Apparatus for preparing specimens for chromatographic analysis

Info

Publication number: US3266554A
Application number: US326743A
Authority: US
Inventors: Gerald K A Brownrigg
Original assignee: Possis Machine Corp
Current assignee: Possis Machine Corp
Priority date: 1963-11-29
Filing date: 1963-11-29
Publication date: 1966-08-16
Anticipated expiration: 1983-08-16

Description

6, 1966 G. K. A. BROWNRIGG 3,266,554

APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIC ANALYSIS Filed Nov. 29, 1963 5 Sheets-Sheet 1 IN VEN TOR.

GERALDKABMWNR/GG A7- TORNEYJ 6, 1966 G. K. A. BROWNRIGG 3,266,554

APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIC ANALYSIS Filed Nov. 29, 1965 5 Sheets-Sheet 2 INVENTOR.

A-rron. N: Y6

5 Sheets-Sheet 3 Aug. 16, 1966 G. K. A. BROWNRIGG APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIC ANALYSIS Filed Nov. 29, 1963 16, 19 a. K- A- BROWNRIGG 3,266,554

APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIC ANALYSIS Filed NOV. 29, 1963 5 Sheets-Sheet 4 q \S) k\ 1477'ORNE Y5 1966 e. K. A. BROWNRIGG 3,266,554

APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIG ANALYSIS 5 Sheets-Sheet 5 Filed Nov. 29, 1963 M Rm 0 Tw mm V00 K P m a 5 A 7-7- oe/vE Y6 United States Patent 3,266,554 APPARATUS FOR PREPARING SPECIMENS FOR CHROMATOGRAPHIC ANALYSIS Gerald K. A. Brownrigg, Golden Valley, Minn., assignor to Possis Machine Corporation, Minneapolis, Minn., a corporation of Minnesota Filed Nov. 29, 1963, Ser. No. 326,743 1 Claims. (Cl. 159-5) The present invention relates to analytical equipment and more particularly to an apparatus for depositing a liquid solution to be tested upon an absorptive medium to be used in conducting chromatographic analysis of the materials either dissolved or suspended in the liquid.

A number of devices have been previously proposed for preparing chromatographic test samples by depositing drops of a fluid at a selected point on a sheet of filter paper. These prior devices have, however, been unsatisfactory in various respects and to some extent ineifective in operation.

One important shortcoming of the prior devices of the type described results from the fact that an undesirable quantity of dust is frequently found to acco-mulate on the surface of the filter paper at the point where liquid is applied thereto. In many cases this deposit of dust is clearly visible to the naked eye and tends to intenfere with the results obtained in the chromatographic test subsequently performed on the paper.

A further shortcoming of some or the prior devices of the type described is that there is no reliable means for securely retaining the filter paper in a selected position upon the apparatus. Occasionally the filter paper will be disturbed by an operator causing a portion of the fluid which is being tested to be applied in one area on the filter paper while the remainder of the fluid is applied at a different location. The test results in such an event would be valueless.

A still further shortcoming of some of the prior devices of the type described is that the evaporation of liquid from the material deposited on the filter paper often requires a substantial length of time and there is no means provided for speeding .up the process. The preparation of test specimens therefore requires excessive time.

Another shortcoming of many of the prior devices of the type described is that the syringe emptying mechanism is positioned immediately above the filter paper which is to receive the liquid from the syringes and as a result the nozzles through which the liquid is deposited cannot be easily lifted away from the filter paper for the convenient removal of old sheets and the insertion of new sheets. A further shortcoming of many of the prior devices of the type described is that the diameter of the test sample applied to the filter paper cannot be accurately and reliably controlled.

In view of these and other defects of the prior art it is a general object of the present invention to provide an improved apparatus for preparing samples for chromatographic analysis, which is reliable in operation, low in cost and rugged in construction.

Another object of the present invention is the provision of an improved liquid depositing and evaporating apparatus of the type described wherein the filter paper upon which the test specimen is deposited is reliably held in a selected position.

Another object of the present invention is the provision of an improved apparatus of the type described in which no dust will collect in the area that liquid is being deposited upon the filter paper.

Yet another object of the present invention is the provision of an improved apparatus of the type described having means for enabling the evaporation rate to be control-led by regulation of the temperature of the air which is circulated for evaporating liquids.

Still another object of the present invention is the provision of an improved apparatus of the type described including an accurate and reliable means for controlling the diameter of the sample deposited on the filter paper.

Yet another object of the present invention is the provision of an improved apparatus of the type described in which the sheets of filter paper can be easily placed in position and the liquid depositing nozzles quickly removed from their operating position when the filter papers are to be removed from the apparatus.

Other objects of the invention will become apparent as the description proceeds.

To the accomplishment of the foregoing and related ends, this invention then comprises. the features hereinafter iiully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.

The invention is illustrated by the accompanying drawings in which the same numerals refer to corresponding parts and in which:

FIGURE 1 is a front elevational view of an apparatus embodying the present invention partially broken away;

FIGURE 2 is a plan view of the apparatus of FIG- URE 1;

FIGURE 3 is a side elevational view of the apparatus partially broken away;

FIGURE 4 is a transverse vertical sectional view taken on line 4-4 of FIGURE 2;

FIGURE 5 is a horizontal sectional view taken on line 5-5 of FIGURE 3;

FIGURE 6 is a partial vertical sectional view taken on line 6-6 of FIGURE 2;

FIGURE 7 is an enlarged partial vertical sectional view taken on line 7-7 of FIGURE 2; and

FIGURE 8 is a vertical sectional view taken on line 8-8 of FIGURE 2.

Referring now to the drawings there is shown in FIG- URE 1, a fluid depositing and evaporating apparatus of the present invention. The apparatus indicated generally at 10 includes a rectangular support or housing 12 having a front wall 14, a rear wall 16, top wall 17,

side walls

18 and 20 and a bottom wall 21. Each corner of the bottom wall 21 has secured thereto a downwardly projected leg 22.

Referring to FIGURE 5, rigidly afiixed within the housing 12 upon the bottom wall 21 is a drive means indicated generally at 28 and including a slow speed drive motor 30 operatively secured to a speed reducing means or transmission 31 which is coupled to an output shaft 33. The transmission 31 preferably includes a clutch (not shown) which will engage only when the motor 30 is operated.

The drive means 28 also includes a high speed drive motor 32 having an output sheave 34. A belt 36 trained about sheave 34 and a sheave 38 affixed to the shaft 33 drivably couples motor 32 to the shaft 33. Also secured to the shaft 33 is a worm 42 positioned in engagement with a worm wheel 46.

As shown in FIGURE 1, the worm wheel is horizontally positioned above the bottom wall 21. Attached to the bottom wall 21 is an upwardly extending generally U-shaped support bracket 48 upon which is mounted a bearing plate 50. Rigidly mounted upon the bearing plate 50 is a journal 52 having a ball bearing 54 recessed in its upper end. The lower portion of the worm wheel 46 is fitted in the inner race of the bearing 54. The upper end of the worm wheel is fitted in a bearing 56 which is itself mounted within a bearing support collar 58 the latter being mounted upon a horizontally disposed plate 60. The worm wheel 46 is provided with a vertically extending threaded bore through the center thereof at 62 within which is threaded a vertically disposed drive member 64.

The upward end of the drive member 64 projects through the wall 17 of the housing 12 as best seen in FIGURE 6. Mounted rigidly at the back of the housing 12 and extending vertically therefrom is a support plate 66. Secured to plate 66 is a vertically positioned bracket plate 68 which encloses the member 64.

Rigidly mounted upon the drive member 64 is a cam 70 including a cam lobe 72 positioned when raised to contact a limit switch 73 connected to the motor 32 by means of conductors 75. The limit switch 73 is normally closed and will be opened when contacted by the lobe 72 thereby turning off the motor 32. Wired to the motor 31 by means of conductors 77 is a normally closed limit switch 79 which is positioned to be contacted by the cam lobe 72 when the operating member 64 is moved to the lower dotted line position of FIGURE 6 thereby turning 011 the motor 30.

Rigidly mounted upon the upward end of drive member 64 is a plate 74 within which is threadedly mounted a plurality of laterally spaced and vertically disposed adjustment screws 76, each adapted to contact the upward end of a syringe plunger shaft 92 as shown in FIGURE 3.

Upon the bracket plate 68 are mounted a plurality of yieldably retaining clips or brackets 81 in vertically aligned pairs. As shown in FIGURE 7, below each pair of retaining clips 81 is mounted a bracket 78 including a horizontal slot 80 within which is mounted a coupling 82 preferably formed from an organic material such as a plastic resin. The couplings 82 are each provided with a central vertically disposed bore 84 within which is mounted a tubular extension 86 of a cylindrical container shown as a graduated syringe 88. The container may be viewed as a reservoir for storing liquid.

Within each of the syringes 88. is mounted for vertical sliding movement a plunger 90 including a vertically disposed plunger shaft 92 as shown in FIGURES 1 and 3. The upward end of each shaft 92 is provided with a head 4 which during operation engages the lower end of one of the adjustment screws 76.

Communicating with each of the bores 84 in the coupling 82 is a flexible conduit such as a small plastic tube 98. Each of the tubes 98 extends to and communicates with an elongated nozzle support housing or closure indicated generally at 108 as shown in FIGURE 4. The housing 108 is formed from a generally U-shaped channel 102 having upper and lower walls 184 and 106 connected by means of a back wall 108. The front wall of the housing is composed of a transparent member such as a glass plate 110 and the housing is closed at each end by means of suitable end walls 112.

The upper wall 104 of the housing 102 is provided with a plurality of spaced apart threaded bores 114 Within which is threaded at each end a removable plug member 116. (FIGURES 2, 4 and 8.) Between the plug members 116 are mounted a plurality of nozzle support assemblies indicated generally at 118.

Each assembly 118, as best seen in FIGURE 4, is composed of a base member 12f} provided with screw threads at its lower end which project into the threaded bores 114. The center of each of the base members 120 is bored at 122 and at 126 to receive an elongated cylindrical coupling member 124 for sliding movement therein along a vertical axis. The coupling member 124 is also provided with a shoulder 128. Between the shoulder 128 and a portion of the bore 122 is provided a resilient means such as a spring 138 for yieldably biasing the coupling 124 in an upward direction. The base member 120 is provided with a vertical keyway 132 into which projects a key 134 adapted to prevent relative rotation between the coupling 124 and the base 128. At the center of coupling 124 is a bore 136 through which the tube 98 projects. Extending over the upward end of the coupling 124 is an adjustment nut 138 threaded at 1411 upon the upward portion of the base 120. As will readily be seen, by turning the adjustment nut 138 in one direction, the coupling 124 and tube 98 can be forced downwardly against the spring 130. When the nut 138 is turned in the opposite direction, the spring will force the connector 124 and the tube 98 upwardly.

Mounted frictionally over the lower end of the connecting member 124 is a neck 142 having a central bore 144 through which the lower portion of the tube 98 extends. The lower end of the tube 98 projects a slight dis tance from the open lower end of the neck 142 to define a nozzle which is positioned during operation a short distance upwardly of an absorbing medium such as a piece of filter paper 150.

The nozzle support housing 108 is also provided with a plurality of bored openings 152 in its lower wall 106 concentric with the lower end of the necks 142. Adjacent the outside of each opening 152 is a circular recess and a shoulder 154 within which is mounted a rubber sealing ring 156. In the top wall 17 in vertical alignment with each of the rings 156 has a bore 158. Rigidly secured in alignment with each bore 158 upon the lower surface of wall 17 is a vacuum connector 160 to which is suitably coupled a vacuum hose 162. As shown in FIGURES 3 and 5, each of the vacuum hoses 162 extends downwardly and is suitably connected to a manifold 164 which is itself rigidly mounted on the bottom wall 21 of the housing 12. A vacuum line 166 is secured to the manifold 164 in communication with each of the lines 162. The other end of the line 166 communicates through a T coupling 168 with a vacuum means composed 'of a vacuum pump 170 connected through a coupling 171 with an electric drive motor 174. To this end, a hose 176 is connected between the inlet of the pump 170 and T coupling 168. Also connected to the T coupling 168 is an air pressure control means such as a needle valve 178 which communicates through a vent opening 180 with the atmosphere. The valve 178 includes an adjustment means composed of a needle 182 afiixed to a control knob 184. With the pump 170 in operation, by turning the knob 184 in a first direction the needle 182 can be withdrawn thereby allowing a greater amount of air to flow through the inlet opening 180 so as to raise the pressure within line 166. By turning the knob 184 in the opposite direction the amount of air passing into the line 166 through the vent opening 180 can be reduced thereby lowering the pressure within line 166 and within each of the lines 162.

Referring to FIG. 2, suitably mounted upon the top of the housing 12 at the rear thereof are a pair of vertically extending

brackets

150 and 152 to which are pivotally secured the rearward ends of a generally U-shaped yok'e 155 upon which housing 101) is rigidly mounted. The yoke 155 includes a central leg 157 and a pair of parallel side legs 158. Secured to the ends of the housing 100 is a portion 168 of a releasable locking means such as a clasp 162 the lower end of which is rigidly secured to the side wall of the housing 12.

Thus, during operation, when the filter paper 158 is to be placed in the apparatus for collecting a fluid sample from the syringes, the nozzle support yoke 155 is raised thereby elevating the housing 100 and allowing the filter papers 150 to be placed in the desired positions substantially as shown in FIGURE 2.

Referring to FIGURE 8, beneath each of the plugs 116 is provided a bore 172 and concentric therewith is a sealing ring 173 which projects downwardly and is adapted to contact a small section of an air filter paper which is provided to clean the air used for evaporating liquid from spots formed on each of the filter papers 150. Beneath each ring 173, the top wall 17 is provided with a bored air inlet opening 177.

The operation of the apparatus will now be described.

To begin the operation the clasps 162 are released and the support arm 154 is raised about the

pivots

150 and 152 until the housing 100 is lifted somewhat above the surface of the top plate 17. At this time, the sheets of

filter paper

150 and 175 are placed in position substantially as shown in FIGURE 2. The'yoke 154 is then lowered and locked in position by means of the clasps 162. The syringes 88 are then filled and the high speed motor 32 is actuated to raise the drive member 64 to the solid line position of FIGURE 6. The plunger of each of the syringes is then inserted and the screws 76 are adjusted so that the plungers are located in exactly the same position in each syringe. The vacuum motor 174 is then started as is the slow speed drive motor 30 which during operation causes the drive member 64 to be lowered at a relatively slow rate. As the syringe plungers are slowly lowered, fluid will be expelled through the open ends of tubes 98 in the form of relatively small drops which after having reached a size sufficient to contact the filter papers 150 will be quickly absorbed thereby.

Assuming, for example, that the open ends of the tubes 98 are raised by adjustment of the nuts 138 to a relatively great distance above the filter papers 170, as for example one-quarter inch, the largest drop which can fall free from the end of the filter paper is from about 7 to 8 mioroliters in volume and will produce a spot of a fairly large diameter on the filter paper. Most operators prefer to form relatively small spots. Smaller spots can be produced by lowering the open end of tube 98 through appropriate adjustment of the nut 138 until the drop being formed at the end of the tube is picked up before it will fall free. In practice, it has been found that a drop can be picked up which is only 2 microliters in volume. The size of the spot formed on the filter paper can be in this manner substantially reduced.

As the motor 30 operates, the motor 174 driving the pump 170 is also operated thereby reducing the pressure on the lower surface of each filter paper 150. The air drawn in through this portion of the filter paper will pass into the housing 102 through the air cleaning filter papers 175 as can be clearly seen in FIGURE 8. The three

motors

174, 30 and 32 will cause the housing to become somewhat warmer than the ambient air and thus comprise a heating means which will function to warm the air drawn in through the bore 172 and air cleaning filters 175. In this way, the evaporation operation can be significantly accelerated. Furthermore, due to the action of the filters 175, there will be no opportunity for dust to accumulate where-fluid is deposited upon each of the filter papers 150. If it is desired to reduce the temperature of the air entering housing 100, it is only necessary to remove the plugs 116 and place a piece of gauze over the opening 114 in which event not as much warm air will enter from the housing 12.

Since the housing 100 and nozzles 118 can be raised simultaneously by the yoke 155, the filter papers 170 can be quickly and easily replaced without disturbing the drive member 64 and the syringe supporting bracket plate 68.

The pressure control knob 184 should be properly adjusted so that the vacuum within the lines 162 is sulficient to draw air through the housing 101) and filter paper 150 but is not strong enough to damage the filter paper or in any way hamper the formation of the spots thereon.

It should. be noted that the operation can be observed through the glass window 110. It has been found important to observe the operation in this manner since the volume of the drops can be judged by the time interval between which drops fall onto the filter paper. Thus, a drop which falls every 22 seconds will have a volume of approximately 2 microliters while a drop that falls every 33 seconds will have a volume of approximately 3 microliters.

It is apparent that many modifications and variations of this invention as hereinbefore set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only and the invention is limited only by the terms of the appended claims.

I claim:

1. An apparatus for depositing fluid on .a coherent sheet-like absorptive medium comprising a syringe including a plunger, a support, bracket means mounted upon said support to hold said syringe, a drive means including a drive motor, a drive member positioned for sliding movement upon said support, a drive assembly operatively connected between the drive member and the drive motor, means on the drive member adapted to engage said plunger, a nozzle, duct means communicating between the syringe and said nozzle, an air-tight housing surrounding said nozzle, said housing including an opening positioned concentric with said nozzle and in vertical alignment therewith on the lower side of said housing, sealing means mounted around the lower aspect of each of said opening, support means positioned beneath the sealing means and adapted to receive said sheet-like absorptive medium between the support means and the sealing means, said support means including an opening in alignment with said opening in the housing and vacuum means communicating with the opening in the support means :for providing an air pressure differential across the absonptive medium.

2. The apparatusaccording to claim 1 wherein a nozzle positioning means is operatively connected between the housing and the nozzle, said positioning means including a threaded base member connected to the housing, an elongated coupling secured to the nozzle and slidably mounted relative to the base member, a resilient member mounted between the coupling and the base member for yieldably biasing the coupling and nozzle in .a first direction and a member operatively abutting against the coupling and threadedly connected to the base member for sliding the coupling and nozzle through the base memher.

3. A liquid depositing and evaporating apparatus for depositing liquid upon a coherent sheet-like absorptive medium comprising in combination a housing, a drive motor mounted within said housing, a liquid discharge assembly operatively connected to the drive motor, said assembly including a liquid storage reservoir, a nozzle means communicating with the reservoir, an enclosure surrounding said nozzle means, said enclosure having an opening therein in its under face and said absorptive medium being adapted to be placed in sealing engagement with said opening, an air suction means for creating an air pressure differential across the absorptive medium moving the air in the enclosure through the absorptive medium, and port means communicating with the enclosure and the interior of the housing whereby the air within the housing is drawn by the suction means into the enclosure and through the absorptive medium to facilitate evaporation of the liquid deposited by the nozzle onto the absorptive medium.

4. An apparatus tfOI depositing liquid from a plurality of syringes upon a coherent sheet-like absorptive medium and for evaporating the liquid therefrom comprising in combination a base support, first and second drive means mounted on the base support, said first drive means being adapted to run at a relatively low speed and said second drive means adopted to run at a relatively high speed, a vertically disposed third drive means operatively connected to each of the first and the second drive means for vertical movement, a horizontally disposed plunger engaging member mounted at the upward end of the vertically disposed third drive means, a plurality of syringes having plungers slidably disposed therein, bracket means on the base support for supporting the plurality of said syringes, adjustable means upon the member for engaging a part of each plunger to vary the extent of movement of the plunger into the syringe, flexible ducts respectively communicating at one end with each syringe, a nozzle at the other end of each of the ducts, a common nozzle support housing connected to each of the nozzles, a yoke movably mounted on the base support and supporting the nozzle support housing for raising and lowering the nozzles, means for selectively changing the spacing between each nozzle and the base support, said nozzle support housing including openings in the lower wall thereof in alignment with each of the nozzles, a sealing means positioned around the openings, said absorptive medium being positioned between each sealing means and the top of the base support, port means in the top of the base support below each of the nozzzles, duct means communicating with each said port means, a source of vacuum communicating with said duct means and a pressure adjustment means communicating with said source of vacuum for regulating the pressure thereof and an air filtering means connected with the nozzle support housing for removing dust from the air before passing through said absorptive medium.

5. The apparatus according to claim 4 wherein the first and second drive means include motors connected to a worm, a worm wheel drivably coupled with said worm and positioned for rotation about a vertical axis, said worm wheel having a threaded opening therein and the lower end of said third drive means being threaded within said threaded opening whereby the rotation of the worm and resultant rotation of the worm wheel will impart vertical movement to the vertically disposed drive member.

6. A liquid depositing and evaporating apparatus for depositing liquid on a coherent sheet-like absorbing medium comprising a housing having a top wall formed with an outlet opening, said coherent sheet-like absorbing medium positioned on said top wall covering said opening, a container for storing liquid, said container having an open top end and a bottom portion having a discharge opening, means supporting the container on the housing, conduit means coupled to said bottom portion for receiving liquid flowing through the discharge opening, nozzle means coupled to said conduit means for receiving liquid carried by the conduit means, enclosure means having a bottom opening positioned on said top wall over the outlet opening enclosing said nozzle means and an upper portion of the absorbing medium, said top wall having an air inlet opening open to said enclosure means, air filtering means covering said air inlet opening, support means on said enclosure means for holding the nozzle means in spaced relation relative to the absorbing medium, means for forcing liquid from the container into the conduit means for discharge through said nozzle means onto said absorbing medium, suction means for establishing a vacuum pressure, conduit means connecting the suction means below said top wall adjacent and surrounding said outlet opening whereby air in the enclosure means is drawn through said absorbing medium and outlet open ing to facilitate evaporation of liquid deposited by the nozzle means on the absorbing medium.

7. The apparatus of claim 6 wherein said nozzle means comprises the discharge end of the conduit means.

8. The apparatus of claim 6 wherein said nozzle support means includes adjustable means for changing the position of the nozzle means relative to the top wall whereby the nozzle means is selectively adjustable toward and away from the absorbing medium.

9. The apparatus of claim 6 wherein said means for forcing liquid from the container includes a plunger means slidably positioned in the container and drive means for moving the plunger means into the container.

10. The apparatus of claim 6 including a yoke member rigidly connected to said closure means and pivotally connected to said housing, said yoke member movable upwardly from the top wall and carrying the nozzle means away from the absorbing medium.

11. An apparatus for depositing liquid onto a coherent sheet-like absorbing medium comprising a housing having a support for the coherent sheet-like absorbing medium, said support having an outlet opening, said coherent sheet-like absorbing medium positioned on said support covering said outlet opening, a container for storing liquid, said container having an open end and a portion having a discharge opening, means attaching said container to a portion of said housing, conduit means coupled to said container portion for receiving liquid flowing through the discharge opening, nozzle means coupled to said conduit means for receiving liquid from the conduit means, support means for holding the nozzle means in spaced relationship relative to the top of said absorbing medium on the support therefor, plunger means movable into the container through the open top end for forcing liquid from said container into said conduit means for discharge through said nozzle means onto said absorbing medium, said nozzle support means including housing means having an air inlet opening and an air outlet opening, said housing means positioned over the support with the air outlet opening covered with the sheet-like absorbing medium positioned on said support, and air suction means connected to said outlet opening on the support below said absorbing medium for drawing air into said housing means through said air inlet opening and out of said housing means through said absorbing medium and outlet opening on the support to facilitate evaporation of liquid deposited by the nozzle means on the coherent sheet-like absorbing medium.

12. The apparatus of claim 11 including means for adjusting the position of the nozzle support means relative to the housing support whereby the nozzle means is adjustable toward and away from the absorbing medium.

13. The apparatus of claim 11 including drive means for moving the plunger means into the container.

14. The apparatus of claim 11 including a yoke member rigidly connected to said nozzle support means, and pivotally secured to said housing, said member movable relative to said housing to move the nozzle means away from the absorbing medium.

15. The apparatus of claim 11 including air filtering means covering said inlet opening of the housing means whereby the air drawn into said housing means by the air suction means passes through said air filtering means.

16. A liquid dispensing apparatus comprising an elongated container stationary for storing liquid, said container having an upper open end and a portion including a discharge opening, plunger means slidably positioned in said container and projected upwardly through said open end, a plate transversely positioned over said plunger means in operative engagement therewith, a drive member secured to the plate means, power transmitting means connected to the drive member for moving the drive member and plate selectively in opposite vertical directions longitudinally of the container, motor means drivably coupled to said power transmitting means for operating the power transmitting means whereby the drive member moves in a first direction carrying the plate means into engagement with the plunger means and moving said plunger means into the container thereby forcing liquid through said discharge opening.

17. The apparatus of claim 16 including control means for said motor means responsive to the position of said drive member for operating the motor means.

18. The apparatus of claim 16 including adjustable means connecting the plate with the plunger means to vary the extent of movement of the plunger means into the container.

19. The apparatus of claim 16 including a support having bracket means for releasably holding said container whereby the container can be separated from the support.

(References on following page) 9 10 References Cited by the Examiner 3,013,591 12/1961 Stanley et a1 141-284 X N TED TAT PATENTS 3,113,103 12/1963 LOWCI'Y 210198 U I S Es 3,192,990 7/1965 Natelson 1595 9/1918 Rogers 141-284 X g; g iii-12g 5 NORMAN YUDKOFF, Primary Examiner. or am Gotham Examzner. 12/1960 Hoyer 141-284 X J. SOFER, Assistant Examiner.

5/1961 Magnuson et a1. 210-198

Claims

1. AN APPARATUS FOR DEPOSITING FLUID ON A COHERENT SHEET-LIKE ABSORPTIVE MEDIUM COMPRISING A SYRINGE INCLUDING A PLUNGER, A SUPPORT, BRACKET MEANS MOUNTED UPON SAID SUPPORT TO HOLD SAID SYRINGE, A DRIVE MEANS INCLUDING A DRIVE MOTOR, A DRIVE MEMBER POSITIONED FOR SLIDING MOVEMENT UPON SAID SUPPORT, A DRIVE ASSEMBLY OPERATIVELY CONNECTED BETWEEN THE DRIVE MEMBER AND THE DRIVE MOTOR, MEANS ON THE DRIVE MEMBER ADAPTED TO ENGAGE SAID PLUNGER, A NOZZLE, DUCT MEANS COMMUNICATING BETWEEN THE SYRINGE AND SAID NOZZLE, AND AIR-TIGHT HOUSING SURROUNDING SAID NOZZLE, SAID HOUSING INCLUDING AN OPENING POSITIONED CONCENTRIC WITH SAID NOZZLE AND IN VERTICAL ALIGNMENT THEREWITH ON THE LOWER SIDE OF SAID HOUSING, SEALING MEANS MOUNTED AROUND THE LOWER ASPECT OF EACH OF SAID OPENING, SUPPORT MEANS POSITIONED BENEATH THE SEALING MEANS AND ADAPTED TO RECEIVE SAID SHEET-LIKE ABSORPTIVE MEDIUM BETWEEN THE SUPPORT MEANS AND THE SEALING MEANS, SAID SUPPORT MEANS INCLUDING AN OPENING IN ALIGNMENT WITH SAID OPENING IN THE HOUSING AND VACUUM MEANS COMMUNICATING WITH THE OPENING IN THE SUPPORT MEANS FOR PROVIDING AN AIR PRESSURE DIFFERENTIAL ACROSS THE ABSORPTIVE MEDIUM.