US 3595252 A
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United States Patent  Inventor Giovanni Contc  References Cited Via A. Sigimbosco 6, Genova-Quin'to, ltaly UNITED STATES PATENTS P 7403 2,628,194 2 1953 Gilwood 210 25  Flled June 26, 1968 2,825,666 3/1958 Stoddard 1 4 134/111 X [451 Patented July 27, 1971  P iority June 28, 1967 3,087,504 4/1963 Gcschkam. 134/111 X  [my 3,276,458 10/1966 lversen et a1 134/1 11 X  71 l7A/67 FOREIGN PATENTS Pal. 803,548 1,249,677 1 1/1960 France 210/96 Primary Examiner-Robert L. Bleutge Attorney-Sparrow and Sparrow APPARATUS FOR CONTROLLED WASHING BY ABSTRACT: Apparatus for controlled washmg of sc1ent1fic DE-IONIZED HIGH-PURITY, RECIRCULATED WATER, PARTICULARLY ADAPTED FOR glassware, articles and materials, comprising an open-topped housing adapted to use the de-ionized water produced by one or more ion exchange columns that are arranged in the lower portion of the housing, such housing being provided, at a certain distance from the base, with a partition on which (without requiring watertight relation) spray-washing can be effected with high-purity water that is collected in a underlying container and is recirculated by a motor-driven pump, and a conductimeter connected in the circuit to afford measurement of the specific resistance of wash water and, therefore, the degree of purity of the individual wash areas.
sum 2 or 2 FIG. 2
l1 3 ii! 5 via INVENTOR ATTORN EY$ APPARATUS FOR CONTROLLED WASHING BY DE- IONIZED HIGH-PURITY, RECIRCULATED WATER, PARTICULARLY ADAPTED FOR SCIENTIFIC GLASSWARE BACKGROUND OF THE INVENTION This invention relates to an apparatus for controlled washing in high-purity deionized recirculated water ll5 megohm), of scientific glassware, or articles, or materials in general, particularly of cumbersome laboratory glassware, such as the sowalled beaker" glasses, balloons, flasks, cylinders and the like.
In the particular art is known an apparatus for the controlled washing (i.e. with detection of degree of purity and cleanliness by measuring the specific resistance of water after the washing operation) in deionized recirculated water of arti cles and materials that are not or slightly water-soluble. which apparatus is exclusively designed for closed-cycle operation, and, therefore, requires that material to be washed be arranged in a sealingly closed container. Practically, this closed cycle apparatus is suitable only for dealing with materials and relatively small articles that are not or slightly soluble and, in the field of scientific glassware, with test tubes and pipettes.
The problem of controlled washing for bigger articles is, however, more diffieult, and for these articles the present invention proposes a functional apparatus of relatively reduced size and advantageously not requiring that the articles to be washed be arranged in a sealingly closed container, with the final satisfactory result of a completely pure washing.
SUMMARY OF THE INVENTION The apparatus according to the invention substantially com prises a housing adapted to use deionized (i.e. demineralized) water producedby a deionizing device having one or more columns of ionexchange resin, which columns are preferably of the mixed layer and interchangeable type. The deionizing device is incorporated within the tank, and this affords recirculation, that is reuse, of wash water by means of a motordriven pump included in the circuit. The system is provided with a conductimeter or the like to measure the specific resistance and check the water before and after the washing operation. The assembly is provided also with piping, valves and fittings for connection to the washing system.
According to an essential constructional feature, developed after various efforts in this specific field, the apparatus of the invention (in order to simultaneously wash a considerable amount of glassware) is adapted for open-cycle operation by using a relatively small housing not requiring watertight closure, and which affords economical and easy washing with high-purity deionized water (l0-l5 megohm) of any scientific glassware, both of small size (test tubes and pipettes) and of larger size and various shapes (such as the so-called beaker glasses, balloons, flasks, cylinders and the like), with the possibility of checking for each article the wash water and hence the corresponding degree of cleanliness. This has been achieved by the provision of conveying the water to be checked to, or as near as possible, an electrode-containing cell that is connected to the conductimeter, which cell is so disposed as not to receive the water discharged from the hous ing, but only the water from the detecting device (or devices, if there are more than one). Contrarily, if the water from the washing device (or devices) falls onto, and flows along, the bottom of the housing, it absorbs too much CO due to the larger area of contact with air, resulting from the spray formations or from the thin layer formations on the bottom of the housing.
Said provision has been sufficient to permit an open-cycle operation, thus limiting absorption of C0,so as to obtain specific resistance values for wash water higher than megohm in a few minutes. Without said provision one could hardly go beyond 0.5 megohm, and this value was obviously too low to enable a check of cleanliness, whereas the value of 5 megohm is sufficiently high to this purpose. Therefore, the method according to the invention (still with more simple constructions that also overcome the drawbacks resulting the necessity of sealed closure) avoids all disadvantages heretofore occurring and enables an accurate check ofcleanliness of glassware.
BRIEF DESCRIPTION OF THE DRAWING A preferred embodiment of the invention is shown, as a nonlimitating example, with reference to the accompanying drawing, wherein:
FIG. I is a diagrammatic elevation of the assembly forming the apparatus of the invention:
FIG. 2 is a sectional view on line 2--2 of FIG. 1 and FIG. 3 is an enlarged view of the drain and perforated disc cover in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing more particularly, the apparatus according to the invention substantially comprises a quadrangular housing 1 made of suitable plastic sheet material, such as reinforced transparent PVC or the like. In the lower portion of the housing, approximately at one-fifth of total height, is cemented a partition or bottom 2 that is inclined toward the center so that all water is conveyed by gravity into the central drain 3 opening into a tank 4 formed by the bottom 2 for a width that is approximately three-fourths of the total width of the housing, and by a transverse wall 6. The central drain in the bottom 2 is constituted by a recessed dish-shaped portion 3 which is formed in the bottom 2 around a hole to the underside of which is fixed an elbow 3a. The dish-shaped portion 3, which is preferably of circular outline, has a stepped marginal edge serving as a seat for inserting therein a perforated disc 3c acting as a strainer. This disc has a central hole for receiving an elbow-shaped pipe 3b coming from a lower cell 7.
The pipe 3b projects upwardly from the perforated disc 30 to an extent enabling the placing therearound of a protecting removable ring-shaped washer 29 and the desired end, depending upon the job to be performed, of the discharge conduits 28, 30 or 31 of washing devices 27, 20 or 21. I
The projecting end of pipe 3b is located at such a level as to avoid that water flowing on the bottom 2 of the housing I may enter the cell 7.
Said cell 7 is fixed to a plate or diaphragm 5a that in turn is fixed by stainless steel screws or bolts to a transverse wall 5 of said tank 4, this wall having to this purpose a suitable opening. An overflow hole is in the upper portion thereof so that all times said cell will be full of water and the electrodes therein will be submerged.
The cell 7 contains two electrodes provided with two perfectly insulated wires that reach a small hole in said diaphragm and project into a chamber 8 underneath partition 2 and adjacent tank 4. The opposed ends of said wires are connected to a megohmmeter 33. Fixed to the diaphragm is a pipe 9 one end of which is bent downwardly so as to dip at a central well 10 in the bottom of tank 4. The other end of pipe 9 is provided with a nipple and projects slightly from the diaphragm so that it can be connected through a hose to a pump 11 in the chamber 8. Said well It) is formed by a suitable, threaded cylinder, welded to the central portion of bottom 6 and closed by a threaded cup-shaped cover. The well 10 enables, through pump 11 and pipe 9, all the water in the tank to be sucked and, if desired, enables the tank to be completely drained by removing the cup-shaped cover. The hose connecting the pipe 9 to the pump 11 must be long enough to permit, alternatively (with the housing in a raised position) a particular connection that will be described hereinafter.
The housing I is supported on a subhousing 12 of the same material and approximately of the same size but of smaller height. Said subhousing is open at the top and serves both to support the housing I and to partially enclose the pump 11, and to enclose the column (or columns) 13 of ion-exchange resin and the attendant connecting pipe, preferably ofthe flexible type.
The outlet pipe 14 from column 13 has two upper bifurcations, one of which is connected to a valve 15 and the other to a nipple l6, and both of them are fixed to, and sealingly pass through, the bottom 2 of housing 1. Through the conduits l7 and 18, the valve 15 and the nipple 16 can be easily connected either to respective washing devices 21 and or to the washwater outlets 18a.
The subhousing 12 is watertight and, therefore, can collect any water leaking from the tank, and if necessary all the water therefrom in case of failure of a connecting pipe. In view of this circumstance, the pump 11 is arranged in an elevated relation with respect to the bottom of the subhousing 12.
The housing 1 is supported on a shoulder welded along the inner side of the upper edge of subhousing l2, and in order to inspect the pump and piping, and to replace the column (or columns) of resin, it can be raised by lateral pivotal movement around hinge means 19.
On the bottom of housing 1 is arranged a device 20 for the washing of pipettes (of the siphon type usually employed in laboratories) and a device 21 for the washing of test tubes. These two devices are connected, respectively, through a conduit 18, a valve 22 and a conduit 23 to the nipple l6, and through pipe 17 to valve 15, respectively. Conduit 18 extends to the upper portion of housing 1 and has a certain number of nipples, one of which is provided with a valve and is connected to device 20 and the others are connected to several water outlets 18a for washing of bigger glassware. The latter is disposed on an intermediate sheet member that is preferably formed by a fixed portion 26 and two removable portions 24 and 25. Through the latter two portions access is permitted to the lower device 21, which can, therefore, be used simultaneously. The device 20 projecting upwardly through member 26, can also be used at the same time as the other wash means. The latter device can be provided with a cover and its discharge opening can be connected to the central drain 3 of housing 1 through a suitable tubular removable extension 3] provided with an end portion in the form of a 90 elbow. This removable extension which may consist of a flexible hose serves to connect the end portion of the discharge pipe to the central drain, so that water can enter directly the pipe 3b leading to cell 7.
The device 21 for washing test tubes substantially comprises a sheet of rigid plastics with suitable edge rims to form a tray of appropriate size. Said tray is provided, on one side, with a nipple for connection to conduit 17. Moreover, the tray is provided with an elevated partition having about lOO circular holes of suitable diameter. Said holes are engaged by an equal number of tube lengths of corresponding diameter, made of rigid plastics, having a top plug with a hole of l2 mm. to permit passage of wash water under pressure in the form of a spray or jet. Test tubes to be washed are placed upside down on these tube lengths. The partition supporting the tube lengths is provided with a peripheral rim of sufficient height to collect the water falling from the test tubes and convey it into a drain pipe 30 having an end portion in the form of a 90 elbow. The water so collected has a reduced area of contact with CO in the air, and when all test tubes will be perfectly cleaned it will reach easily such values of specific resistance as 56 megohm.
If it is desired to check or detect the quality of circulated water, device 21 must be moved toward the center until the elbow of its discharge pipe 30 will register with the central drain opening 3 in the housing, so that water can enter directly into the small tube 3b connected to cell 7. The check of wash water in the various devices is to be made separately, inasmuch as the single cell 7, obviously, cannot receive water from two different devices simultaneously.
In order to check the efficiency of the resin in the column (or columns) 13a removable tubular extension is provided (not shown) affording to easily and directly connect a funnel 27 to one of the outlets 18a. The normal values of specific resistance of column (or columns) 13 are preferably from 15 to 20 megohms, and when these values fall below 5 megohms proper cleanliness is no longer possible and the column (or columns) must be replaced. in order to fill the tank 4 with water to be recirculated, it isjust necessary to pour the necessary amount of water (for example 2025 liters or more), preferably deionized, into the tank; water discharges directly into the tank 4 through the drain 3, whereafter the pump 11 can be started, the megohmmeter 33 inserted for initial check of the efficiency of the column (or columns), and the washing operation can begin.
By suitable actuation of the appropriate valves, an easy control can be effected to the various washing devices which have been previously loaded with glassware and articles to be washed.
It will be understood that changes and improvements may he made to the embodiment hereinbefore shown and described without departing from the spirit of the invention.
1. An apparatus for controlled washing of laboratory glassware, articles and materials that are substantially not water soluble by means of high-purity demineralized recirculated water of substantially 10 to l5 megohms resistance, said apparatus comprising a housing substantially consisting of a transparent plastic material, said housing having a partition cemented therein, said housing having also a plurality of movable washing devices for washing particular articles, a drain in said partition, a collecting tank formed on the underside of said partition by said cementing, a motor-driven pump for recirculating said demineralized water, a demineralizing device having at least one column of ion-exchange resin, said column being preferably one of the mixed layer interchangeable type, and an electrode-containing cell and a conductimeter connected to said cell, said conductimeter measuring the specific resistance and quality of said circulating water, said recirculation in said apparatus consisting of a system of pipe lines, flexible conduits and said pump whereby said demineralized water is taken from said tank by said pump, delivered through said demineralizing column and through said system of pipe lines into said housing and into said plurality of devices for washing of said articles wherefrom said water is returned through said drain into said tank for being recirculated therefrom.
2. An apparatus according to claim 1, said housing being open at the top and said drain being centrally located in said partition, said drain discharging water by gravity into said collecting tank.
3. An apparatus for controlled washing of laboratory glassware, articles and materials that are substantially not water soluble by means of high-purity demineralized recirculated water of substantially 10 to 15 megohms resistance, said apparatus comprising a housing substantially consisting of a transparent plastic material, said housing having a partition cemented therein, said housing having also a plurality of washing devices for washing particular articles, a drain in said partition, a collecting tank formed on the underside of said partition by said cementing, a motor-driven pump for recirculating said demineralized water, a demineralizing device having at least one column of ion-exchange resin, said column being preferably one of the mixed later interchangeable type, and an electrode-containing cell and a conductimeter connected to said cell, said conductimeter measuring the specific resistance and quality of said circulating water, said recirculation in said apparatus consisting of a system of pipe lines, flexible conduits and said pump whereby said demineralized water is taken from said tank by said pump, delivered through said demineralizing column and through said system of pipelines into said housing and into said plurality of devices for washing of said articles wherefrom said water is returned through said drain into said tank for being recirculated therefrom, said plurality of washing devices and said electrode-containing cell having means for receiving only the water from said washing devices to be checked.
said cell being fitted in said washer for being reinforced and protected thereby and a vertical removable conduit having a funnel at the top thereof, said conduit fitting over said tubular extension, projecting beyond and held vertically by said central removable partition.
6. An apparatus according to claim 4, and a removable discharge conduit on each of said washing devices, each of said conduits disposed to fit over said tubular extension when the respective one ofsaid washing devices is being used.