US 3389712 A
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Description (OCR text may contain errors)
F. W. JOHN June 25, 1968 RINSER 2 Sheets-Sheet l Filed Sept. 9, 1966 FREDERICK W. JOHN 0%@ f .am
ATTORNEY' June 25, 1968 F. vv. JOHN 3,389,712
RINSER Filed Sept. 9, 1966 2 Sheets-Sheet 2 INVENTOR FREDEmCK w. JOHN ATTORNEYV United States Patent O 3,389,712 RINSER Frederick W. John, Rochester, N.Y., assignor to The Nalge Company, Inc., Rochester, N.Y., a corporation of New York Filed Sept. 9, 1966, Ser. No. 578,351 12 Claims. (Cl. 134-166) This invention relates to a novel improved automatically cyclical rinsing apparatus for washing laboratory pipets and the like.
The need for apparatus capable of thorough quick low cost rinsing of laboratory instruments such as pipets has long existed. Cleaning of pipets or like laboratory instruments by lhand is relatively costly in time and money, besides being subject to reliability of personnel hand rinsing or washing such used equipment, and tying up equipment and personnel which could be used for other projects. Also, hand rinsing and cleaning pipets or like laboratory equipment is likely to result in considerable breakage with attendant possibility of injury.
To overcome these and other deficiencies of hand rinsing an automatic pipet rinser capable of repetitive rinsing of pipets or like laboratory equipment has been successfully marketed for some time by The Nalge Company of Rochester, New York (of which applicant is chief engineer), as shown on page 12 of Nal-ge Catalog No. 1 1060. That prior rinser apparatus provides for automatic siphon dischar-ge of the rinsing water when it attains a predetermined elevation in the rinsing compartment, with automatic re"- petitive operation, and limits breakage or damage of pipets. However, that prior Nalge automatic pipet rinser is relatively costly to fabricate and has a number of structural and functional disadvantages -which have been known to laboratory equipment users and suppliers for some time. For example, such prior automatic rinsing apparatus is not capable of positively preventing backiiow of contaminated rinsing liquid into the -water supply whereby extra precaution must be taken to comply with some sanitary codes. Also it does not provide a reservoir. for limiting backow which occurs at the end of the rinsing operation, to insure against re-soiling of the cleaned equipment.
It is therefore a primary object of this invention to provide a new improved Siphon type automatic rinser for pipets and like laboratory equipment which solves various shortcomings of, and provides various advantages over, prior available methods and apparatus for rinsing pipets and the like.
More particularly, it is an object of the present invention to provide a novel automatic siphon type rinser apparatus incorporating a main container plus a cooperating water inlet tube and pair of water outlet tubes in a manner so that inlet water will be accumulated around the pipets so as to maximize hydrostatic head and rate of Siphon discharge of the -water for rapid surging and increased cleaning eftectiveness, on a repetitive time cycle, without attendance. It is a related object to provide such a rinser in which the water inlet and outlet means are designed to assure a high rate of rinse water ow at the end of the siphon discharge cycle to assure effective wasliing of lower portions of pipets or the like disposed in the rinser, and also to assure discharge of rinse water from below the lowest portion of the pipet basket used to load and unload the rinser.
It is another object of this invention to provide such an automatic rinser in which the point at which rinse water enters the main pipet basket container is at a vertical elevation above the Weir between the Siphon tubes, thereby positively preventing contaminated rinse water from being able to fiow back into the Water supply, as required by some sanitary codes.
It is still another object to provide such a rinser incor- 3,389,712 Patented June 25, 1968 ice arranged in conjunction with a sump in the main container so that the sump accommodates all rinse water backtiow upon break of the siphon discharge sta-ge, thereby pre-venting contaminated rinse water from contacting pipets or like items in the rinser loading basket.
It is another principal object of this invention to provide such a new improved pipet rinser apparatus lwhich in effect incorporates four tubes (main container, water inlet tube, and two siphon tubes) whereby the main part of the rinser can be integrally blow molded by a new technique hereafter more fully discussed, thereby achieving a major breakthrough in reduced cost of production for such rinser apparatus. It is a related object to provide such an improved rinser apparatus and method for making same wherein the entire rinser comprises only two parts, namely the aforementioned integral blow molded made portion and a simple injection molded base for the same which may be made at low cost and quickly assembled by relatively unskilled workers. l
These and other objects and advantages of the invention will become more apparent upon reference tothe -following description and claims and appended drawings, wherein:
FIGURE 1 is a perspective view of a new improved rinser apparatus constructed according to the invention;
FIGURE 2 is a vertical section of the main body of the rinser in FIGURE l, illustrating in detail the structural relationship of various components (without the base, and along line 2--2 in FIGURE 4);
FIGURE 3 is a bottom plan view looking along the plane 3 3 of FIGURE 2, illustrating the relationship of the discharge tube to the container bottom;
FIGURE 4 is a horizontal cross sectional view taken along the line 4-4 of FIGURE 2, and illustrates the construction of inlet and siphon tubes and formation ofa siphon port in a -well at the bottom of the container;
FIGURE 5 is a partial vertical section and elevation view taken substantially along the line 5-5 in FIGURE 2, and illustrates the arrangement at the end of the water inlet tube for converting input water from a jet stream into a spray falling upon the pipets or other laboratory instruments contained in the main rinser compartment;
FIGURE 6 is a perspective view of the rinser base shown in FIGURE l; and
FIGURE 7 is a perspective of a pipet basket which is removably receivable within the main compartment of the rinser shown in FIGURE l, with parts broken away to illustrate the perforated bottom thereof for passage of rinsing water.
Referring especially to FIGURE l of the drawings,` there is shown a rinser device made according to this invention, generally indicated by the numeral 10. The rinser 10 includes a main body section 12 providing a rinser tub or compartment 13 mounted on an upright base 14. i
Referring more particularly to FIGURES 2 through 5, main body section 12 has a substantially cylindrical section 13 for most of its length, with an attached bottom section 16 including a sloped bottom 16a and other structural features more fully described later. The height of cylinder 13 may be varied according to particular intended applicatioin, and to rinse pipets, chamber 12 would have a height capable of accommodating standard sized commercial pipets, eg., 16-33 inches, loaded through the 3 open top 32. As shown in FIGURES l, 2. and 4, extending vertically along the cylindrical side wall 13 of rinser body 12 is a rinse water inlet tube or duct 18 which is integrally joined to the outer surface of cylindrical section 13 of rinser body 12 by a narrow web 19, with a suitable cross sectional shape and area. A grooved or threaded connector 20 is xedly attached to the lower terminal end of inlet tube 18 for direct or indirect connection to a fresh water source. Water inlet tube 18 extends vertically to an elevation above the open top 32 of cylindrical section 13, and has an upper portion 22 having a coniiguration as shown in FIGURES 1, 2, and 4. Thus, the upper tube end 18a is angularly disposed upwardly and outwardly of the cylindrical chamber 12, and is then turned back upon itself in substantially a U-shaped bend at 22 to direct the water passing therethrough into the cham'ber 12. As shown in FIGURE 2, the U-shaped bend or turn 22 has a radius of curvature at 23 so that input water emerging from inlet tube 18, 18a, 22 is redirected to impinge on a delta shaped splash plate 26 which is formed to one side of a hood-like inlet port 30 substantially at the junction of cylindrical chamber 13 and the end of inlet duct bent end 22. Thus, input water hits splash plate 26 as a jet which is broken up so that the fresh rinse water splashes and cascades in spray form upon the pipets or other objects contained in tube 12, thus avoiding impinging a jetlike stream of input rinse water directly onto the pipets or like objects within the rinser body 12.
Referring to FIGURES 2, 3, and 4, the bottom section 16 of rinser body 12 includes a sloped bottom 16a with a plurality of sloped risers 42, 44, 46, and 48 extending upwardly from sloped bottom 16a and terminating in substantially coplanar projections 41a, b, c, and d, thus providing a horizontal base or floor for receiving a basket such as shown at 70 in FIGURE 7 containing the pipets for rinsing. Also, the sloped bottom 16a and spaces between risers 42, 44, 46 and 48 form a well or sump 52, which has suicient volume (due to diameter across bottom 16a andrheight of walls formed by sloped risers 42, 44, 46 and 48) to accommodate water backing up after termination of siphoning action hereafter described, so that no contaminated rinse water will reach the pipets, or
other instruments, contained in the basket 70 which rests` upon door 41a-d of rinser body 12 as later discussed.
As illustrated in FIGURES 2 and 4, a suitably shaped aperture or passage 54 is formed in well S2, providing a liquid passage between rinser chamber 13 and a pair of discharge siphon tu'bes or ducts 58 and 62. Tube 58 extends vertically along the outer wall of cylindrical rinser chamber 13, secured thereto at web 57a, preferably at a position diametrically opposite to that of water inlet tubev 18 so that rinser body 12 may be integrally made by blow molding as hereafter discussed.
As shown in FIGURES 2, 3, and 4, siphon tube S8 is formed with vertically extending front and back walls 57 and 59 respectively and sidewalls 53; theA lowermost end of front wall 57 converges into well 54, as do the lower ends ot sidewalls 53, and back wall 59 is connected to bottom section 16a in a gradual curve. Rinser bottom 16a is downwardly sloped to opening 54 so that well 52 is formed with its deepest portion feeding the siphon discharge tubes 58-62 for most efficient removal of rinsing water from chamber 12.
Upwardly directed siphon tube 58 is connected to the downwardly directed siphon tube 62 by a vertically extending web 60 with intermediate U-section 61 lbetween upward tube 58 and downward tube 62. The siphon tubes 58 and 62 are of rectangular or other suitable cross section as shown, but each of siphon tubes 58 and 62 has a substantially larger cross sectional area than that of inlet tube 18 to provide a considerable greater rate of volumetric ow through the siphon discharge than the Water inlet as hereafter amplified.
Web 60 extends between upwardly directed siphon tube 58 and downwardly directed Siphon tube 62 to a point of junction 66 between these tubes below interconnecting U-section 61. The cross sectional area at junction 66 and U-section 61 is at least as great as that of -tubes 58 and 62; and the height of these components 61, 66 controls the siphoning action between duct 58 and 62, as well as being a factor in determining rates of siphon discharge.
The lower end of downward siphon tube 62 terminates in a suitable grooved or threaded siphon outlet nozzle or tting-72 adapted for connection by flexible tubing or like means to a suitable drain. As shown in FIGURES l, 2, and 6, siphon discharge tube lower section 62a extends below the bottom 16a of rinser body 12; tube 62-62a preferably is oriented so that outlet connector 72 is in line with inlet tube 18 and connector 20, whereby rinser body 12 can be integrally blow molded as hereafter discussed. As shown in FIGURE 2, a web 60a is provided between the outlet duct 62a and the rinser bottom 16a for added strength (a portion of web 69a may fbe open or discontinuous to save material if desired). Positioning the outlet connector 72 of siphon duct 62-62a substantially below the bottom 16a of rinser body 12 provides an increase in differential water pressure head which speeds up the siphoning discharge rate for more efficient pipet rinsing, especially at the end of a discharge cycle, and also assures that the siphon discharge tiow will empty rinser chamber 1 3 to a level below projections 41o-d forming the supports for pipet basket 70.
Previously described well 52 at the bottom of rinser body 12 has at least enough volume to provide a reservoir which can accommodate all of the water which is contained inA upwardly extending siphon tube 58 during siphon discharge actiony and would not be siphoned out when the siphon breaks That is, when siphon discharge action causesy the water` in rinser chamber 13 to fall below the level of outlet 54 communicating with upward siphon tube 58, air would be sucked into tube 58 causing a siphon break, whereby water contained in upwardly extending siphon tube 58 below junction 66 will tiow back along tube 58 into well S2. Because the pipet basket 70 is vertically positioned on lioor segments 41a-d, above well 52, contaminated rinse water received within well 52 does not contact the cleaned instruments.
As shown particularly in FIGURE 2, the top 61, 66 of siphon ducts 58 and 62 is vertically below the inlet aperture 22a at the upper end of inlet duct 18, the latter also being above top edge 32 of rinser chamber 13. Since the rinser 10 will undergo siphon discharge action when the level of water in rinser chamber 13 rises above siphon U-section 61, this difference in elevation between rinse water inlet port 22a and the siphoning tubes 58-61-62 insures against aback tiow of contaminated rinse water into inlet water duct 18 and the water source. Also, inlet water contamination is prevented in the event of a blockage in the siphon tubes 58-61-62, as water would then overflow upper end 32 of rinser compartment 13.
Looking now to FIGURES 1, 2, and 6, main rinser body 12 is mounted on a base 14 in upright position, with lower siphon outlet duct 62a extending through base 14, in a manner ,now amplified. Turning to FIGURE 6, base 14 comprises a cylindrical upright section 92 having a suitable downwardly sloped conical base ange section 98 formed integrally therewith. Base 14 is provided with a suitably shaped aperture 96 in cylindrical side wall section 92 near the top of conical base ange 98, as shown. A slot 94 is provided in cylindrical section 92 at its upper edge, at a position diametrically opposite and above opening 96. Slot 94 extends downwardly from the top of cylindrical section 92 a suitable distance to receive and support the lowermost portion of siphoning ducts 58 and 62 with the underside of duct section 62a resting on the horizontal slot section 94a. Upon insertion of rinser body 12 into base 14, rinser body 12 is manipulated so that siphon outlet tube section 62a and end connector 72 project through lower opening 96 while siphon ducts 58 and 60 are seated within slot 94.
Referring especially to FIGURE 2, rinser body 12 is provided with a ange or shoulder 17 extending circumferentially around the lower end of cylindrical chamber 13 at its junction with bottom 16, just below web 19 and inlet duct 18 (excepting in the region of siphon tubes 58 and 62). This shoulder 17 provides means for seating rinser body 12 upon base unit 14, with the upper edge 100 of cylindrical base member 92 being contiguous with shoulder 17 to provide solid support. To prevent accidental disengagement of the main rinser body 12 from base 14, the two are preferably secured together by spot welding them at selective points, or by any other suitable means for xedly connecting them together.
Turning now to FIGURE 7, thereis shown a suitable pipet basket 70 used to facilitate loading and unloading pipets 80 into and from rinser chamber 13. Basket 70 is of a type known to the art (see aforementioned Nalge catalog), and is therefore shown and described herein only to extent necessary for illustrating the present invention. As shown, basket 70 includes a main cylindrical shaped container 72 having a cylindrical projecting section 74 of reduced diameter extending therefrom, with a handle 76 suitably attached to cylindrical section,74 as f shown. The lower portion of cylindrical container 72 is provided with a perforated bottom 82 to permit the ow of rinsing water therethrough. Dirty pipets 80 or the like are loaded into basket 70, and the basket 70 is placed on the oor sections 41a-d of the rinser 10 prior to initiation of the rinsing cycle.
Summary of operation Fresh water inlet connector 20 is connected by suitable means, such as flexible piping, to a fresh water source, and siphon outlet connector 72 is similarly connected to a suitable drain for discharge of used rinsing water. A pipet lled basket 70 is placed in rinser chamber 13 as discussed and automatic cycle rinsing is initiated by turning on the fresh water source, whereby water flows through inlet tube 18 and is redirected by surface 23 in the U-shaped inlet tube section 22 to impinge on the splash lplate 26, whereby the jet-like water input is broken up into a water spray which falls into rinser chamber 13 and begins to ill it. The water inlet tube 18 has a suitable cross section to permit a suitable volumetric rate of flow of input water with normal laboratory water sources. The input water will fill rinser chamber 13 at a predetermined volumetric rate, and at the same time water will pass through outlet port 54 and rise in upward siphon tube 58 at the same rate. When the water rises inv rinser chamber 13 and in siphon tube 58 to the height of junction 66 and then to the inside of U-section 61, `siphoning action is automatically initiated as water ows from duct 58 down siphon discharge tube 62. Thus, with siphon ducts 58 and 62 lled, there is then a continuous siphoning of water from rinser chamber 13. Since the inner cross section area of each of siphon tubes S8 and 62 is substantially greater than the inner cross section area of inlet water `duct 18, the volumetric rate of flow of water through siphon ducts 58 and 62 is substantially greater than it is in inlet water tube 18. The volumetric rate of ow through siphon ducts 58 and 62 is sufciently greater than the volumetric rate of water input into rinser chamber 13 so that water in main chamber 12 rapidly surges down through the pipets 80 in basket 70 and is discharged from the lowermost portion of chamber 13 at opening 54 in rinser well 52. Since the discharge end of siphon duct 62 terminates substantially below the bottom 16a of rinser chamber 13, there is a continuing rapid water discharge from rinser chamber 13 so that water rapidly surges through the lower portion of pipets 80 in basket 70, since the siphoning action continues until rinser chamber well 52 has been evacuated due to continuing dlerential hydrostatic head which drives the siphon. As water is eliminated from well 52, air is sucked into aperture 54 breaking the siphon action, whereafter water contained in upwardly siphon'duct 58 will fall back into chamber 13 but is totally retained within well 52. In the meantime, water falls into chamber 13 from inlets 18, 22, 30, and plate 26,v
and the cycle can be automatically repeated as often as desired. The volumetric rate of discharge ow through siphon ducts 58 and 62 is a function of the head of water between the outlet connector 72 and the liquid level in chamber 12, which is substantially equal to the height of section 66 at the beginning of the siphoning action and thereafter decreases as the water level in the rinser chamber 13 progressively decreases due to siphoning from the chamber 13, until the water in the chamber is lowered to expose the outlet port S4 to atmosphere and break the siphon. In operation of a typical unit connected to a typical source of fresh rinsing water, the siphoning action is automatically repetitive at about a 60 to 70 second rate per rinsing cycle, depending upon the size of the rinsing chamber, etc., thus providing automatic, rapid, repetitive surging of water through the pipets, or the like, for as many rinses as is desired.
Upon completion of the desired number of cycles to satisfactorily wash pipets 80, the basket 70 may be removed fromrinser chamber floor sections 41a-d which maintain basket 70 above well 52 and the back flow from duct 58 of contaminated rinse Water. l
An illustrative suitable rinser 10 would h ave a main body with chamber 13 about 18 inches high and 6 inches in diameter and base well section 16 about 21/2 inches high, with other components proportional thereto and with configuration as illustrated and described.
Rinser 10 may be made of any suitable material which is capable of withstanding considerable physical abuse, usage, and corrosion under a widely varying temperature range. A preferred embodiment is made of conventional commercial polyethylene of low, medium or high density.
The rinser base 14 is preferably made inone piece by injection molding. The rinser body 12 may be made of individually molded or otherwise fabricated sub-components which are welded together in a manner apparent to one skilled in the art in light of the disclosure herein. The new improved rinser 10 made in such manner will achieve the various objectives and advantages discussed above.
However, an important aspect of this invention is to provide a novel rinser 10 incorporating a novel rinser body 12 which can be made as an integral unit including main container section 13, tubes 18, 58, 62, and 62a, and base section 16 by blow-molding the same from a single parisorl. using an extension of the method and apparatus disclosed in my co-pending United States application, Ser. No. 477,692, filed Aug. 6, 1965, entitled Methods, Apparatus and Products. v
The invention may -be embodied in other specific forms without departing from the spirit or essential characteristic thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which corne within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
What is claimed and desired to be secured by United States Letters Patent is:
1. A rinser apparatus comprising: a main rinser chamber adapted to receive objects to be rinsed; a well below said main rinser chamber having a floor with a plurality of support means extending upward from said oor and adapted to support objects disposed in said main rinser chamber; water inlet means for supplying water to said main chamber; siphon means including a rst siphon tube having its lower end connected to said well through an aperture therein and a second siphon tube connected to the upper end of said first tube and extending downwardly therefrom, the cross-sectional area of each of said siphon tubes being greater than the cross-sectional area of said water inlet means, and the volume of said rinser well below the level of said support means being greater than the volume of said first siphon tube.
2. A rinser apparatus as defined in claim 1 wherein said water inlet means is vertically located above the highest vertical point of said siphon means.
3. A rinser apparatus as defined in claim 2 further comprising: splash means associated with said water inlet means so that input water is directed against said splash means and thereafter cascades downwardly into said main rinser chamber.
4. A rinser apparatus as defined in claim 1 wherein said second siphon tube extends a substantial distance below said aperture in the floor of said rinser well connected with said lower end of said first siphon tube, said distance being sutiicient to provide a substantial head to drive the siphon as the water level in said main rinser chamber decreases to below the level of said support means rising from the floor of said well.
5. A rinser apparatus as defined in claim 1 wherein said water inlet means comprises a tube joined to and extending vertically along said main rinser chamber to a point above the highest vertical point of said siphon means.
6. A rinser opparatus as defined in claim 1, wherein: said second siphon tube extends a substantial distance below said aperture in the fioor of said rinser well connected with said lower end of said first siphon tube, said distance being sutiicient to provide a substantial head to drive the siphon as the water level in said main rinser chamber decreases to below the level of said support means rising from the floor of said well; said water inlet means comprises a tube joined to and extending vertically along said main rinser chamber to a point above the highest vertical point of said siphon means; and said water inlet tube and said first and second siphon tubes are substontially aligned with each other and with the center of said main rinser chamber.
7. A rinser apparatus as defined in claim 6, said rinser apparatus being integrally blow-molded from plastic material.
8. A rinser apparatus as defined in claim 7, further comprising a base for said .integral blow-molded rinser.
`9. A rinser apparatus as defined in claim 8, wherein: said second siphon tube has an outlet portion extending across and below said rinser well bottom in substantial alignment with said linet tube and first and second siphon tubes and center of said main rinser chamber; and said base is substantially hollow and includes means for supporting modating said first and second siphon tubes, and apertured means for accommodating said outlet end of said second siphon tube.
10. A rinser apparatus comprising: a rinser chamber having vertically extending sidewall and bottom and adapted to receive objects to `be rinsed; water inlet means -for supplying water to said rinser chamber; siphon means including a first siphon tube having its lower end connected to an aperture in the bottom of said rinser charnber and ya second siphon tube connected to the .upper end of said first tube and extending downwardly therefrom, the cross-sectional area of each of said siphon tubes being greater than the cross-sectional area of said water inlet means; said water inlet means being disposed above the highest point of said siphon means; and a splash plate in association with said water inlet means so that input water is directed against said splash plate and thereafter cascades downwardly into said rinser chamber; lsaid second siphon tube extending below said aperture in the bottom of said rinser chamber connected with the lower end of said tirst siphon tube a distance sufficient to provide enough head to drive the siphon as the water level in said rinser chamber decreases towards the lbottom thereof; said water inlet means and said first and second siphon tubes being substantially aligned -with each other and with the center of said vrinser chamber.
11. A rinser apparatus as defined in claim 10, wherein the above described rinser components are integrally blow-molded from plastic material, and said apparatus further comprises a base for said integr-al blow-molded rinser.
12. An apparatus as defined in claim 11 wherein said second siphon tube has an outlet portion extending across and below the rinser bottom in substantial alignment with said inlet means and first and second siphon tubes and the center of said rinser chamber; and said base is substantially hollow and includes means for supporting part of the rinser chamber sidewalls, means for accommodating said first and second siphon tubes, and means for accommodating lthe outlet end of said second siphon tube.
References Cited UNITED STATES PATENTS 5/1943 Brown et al. 134-166 4/1960 Richheimer 134-166XR FOREIGN PATENTS 1,017,929 12/1952 France.