AU634468B2 - Medical fail safe releasible locks and/or seals for capped disposable centrifuge containers, cryogenic vials and the like - Google Patents

Description

AUSTRALIA

PATENTS ACT 1952 634468 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: Actual Inventors: Address for Service: MULTI-TECHNOLOGY INC.

175 South West Temple, Salt Lake City, Utah 84101, U.S.A.

1) Paul M. Jessop 2) David H. Jeffs ARTHUR S. CAVE CO.

Patent Trade Mark Attorneys Level Barrack Street SYDNEY N.S.W. 2000

AUSTRALIA

Complete Specification for the invention entitled MEDICAL FAIL SAFE RELEASIBLE LOCKS AND/OR SEALS FOR CAPPED DISPOSABLE CENTRIFUGE CONTAINERS, CRYOGENIC VIALS AND THE LIKE.

The following statement is a full description of this invention including the best method of performing it known to me:- 1 ASC 49 ii la Bff B~C u qi rr~a~- Field of Invention The present invention relates generally to disposable laboratory testing devices, and more specifically to fail safe releasible locks and seals for relatively small capped centrifuge containers, cryogenic vials and the like.

Prior Art The need for centrifuging certain specimens and cryogenic vials, within the scientific community, in conventional processes of analysis has long been prevalent. The problem is that the inteqrity of the end closurI snmetimes fails tunder intense centrifugal force or when the container, with the specimen therein, is boiled or frozen.

Without closure integrity, researchers, medical personnel and others are exposed to many extremely harmful or even lethal organisms, such as the AIDS virus. Radioactive contamination of medical personnel is a further risk. Large areas can become contaminated. Furthermore, the accuracy of specimen testing is often tied to the exact volume of the specimen undergoing testing. When part of the volume is lost during testing because the lid or closure of the container, tube or vial leaks, the accuracy of the test is lost.

Prior art containers and vials with removable closures have been used for many years to perform centrifuging, boiling and freezing as part of laboratory testing procedures. These have la i been lacking in some important areas. The two most significant limiting areas are closure integrity and the ability to accurately and immediately ascertain when the closure is fully closed and sealed. Some prior art containers have failed to maintain closure integrity during specimen processing, and some do not advise the laboratory technician when the seal hss been maintained.

With an increasing concern for the hazards of scientific research and the need for accuracy through preservation of the volumetric integrity of specimens placed in centrifuge containers and vials, the foregoing concerns constitute problems not solved by the prior art which are addressed by the present invention.

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Ilsl 0670v/MS 3 BRIEF SUMMARY OF THE INVENTION In one form the invention is a specimen container for receiving a biological sample to be processed by centrifuging, boiling, freezing and the like during laboratory testing and shipping, comprising a tubular container including an open proximal end, a closed distal end and an interior wall of straight, noncurving tubular configuration, and a cap formed from a resilient polymer material and being releasably engageable with the open proximal end, said cap having a flange portion configured to extend across the proximal end of the container and a male portion coupled to a bottom side of the flange portion and projecting downward such that the male portion extends into the hollow of the container at the open proximal end when in a closed configuration, said container being characterized by said male portion comprising a skirt member formed from a resilient plastic material which divergently tapers from a juncture with the flange portion of the cap, to a lower edge of the skirt member which seals the container by being in direct contact with the straight, noncurving configuration of the interior wall of the container and further comprising an O-ring compressed in direct contact between the tubular wall adjacent the open proximal end, (ii) the upper portion of the skirt member and (iii) the flange portion of the cap.

In another form the invention is a method of sealing a specimen within a tubular container having an open proximal S end, a closed distal end and an interior wall of straight, noncurving tubular configuration and an exterior lip and cap S at or near said proximal open end comprising the steps of: a) imposing sealing means internally between the cap and container to create a seal; b) laterally inserting a resilient, plastic releasable lock jointly enclosing the lip and a top rim of the cap within a receiving channel section of the lock to r i 1 i I i~ rs~r 7 0670v/MS 4 interlock the cap and lip to retain the seal during processing of the specimen; and wherein said cap formed from a resilient polymer material and being releasably engageable with the open proximal end, said cap having a flange portion configured to extend across the proximal end of the container and a male portion coupled to a bottom side of the flange portion and projecting downward such that the male portion extends into the hollow of the container at the open proximal end when in a closed configuration, said container being characterized by said male portion comprising a skirt member formed from a resilient plastic material which divergently tapers from a juncture with the flange portion of the cap, to a lower edge of the skirt member which seals the container by being in direct contact with the straight, noncurving configuration of the interior wall of the container and said sealing means is an O-ring compressed in direct contact between the tubular wall adjacent the open proximal end, (ii) the upper portion of the skirt member and (iii) the flange portion of the cap.

*iiil BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective of a centrifuge container with a tethered cap illustrated as being disposed in its fully sealed position; Figure 2 is a fragmentary side plan view illustrating the preferred tether connector between the container and lid of Figure 1; Figure 3 is an exploded perspective of a releasible externally-applied lock, according to the present invention, about to be placed upon the container of Figure 1 and its closed cap; Figure 4 is an exploded perspective of the releasible lock of Figure 3 fully placed upon the container of Figure 1 and its closed cap; and Figure 5 is a cross-section of an internally-disposed seal interposed between a centrifuge tube an a lid thereof, which may be used alone or in conjunction with the externally-applied lock of Figures 3 and 4.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Reference is now made to the drawings, wherein like numerals are used to designate like parts throughout. Specific reference is made to Figure 1 which comprises a perspective representation of a centrifuge container assembly, designated generally 10. It is to be understood, as used herein, that the term container may mean a test tube, a centrifuge container, a cryogenic vial or the like. Containpr assembly 10 is iIunstratpd as comprising a tube and a cap closure system. Container 10 is illustrated as being generally cylindrical in shape. It is to be appreciated that the container and lid disclosed herein are exemplary. The present invention applies to almost all specimen containers which have caps, plugs or lids for use in centrifuging, boiling, freezing and like testing processes and during shipping.

The container assembly 10 comprises a small cylindrical tube, generally designated 15, a cap or lid, generally designated 17, adapted to close upon the open top of the associated tube and a tether, generally designated 19, by which the associated tube 15 and cap 17 are connected. The entirety of the disposable container assembly is formed as one piece from a suitable synthetic resinous material, such as polypropylene, using known injection molding techniques.

Tube 15 comprises a central elongated hollow cylindrical wall 16, which is illustrated as being of uniform thickness throughout. Wall 16 thus comprises inside annular surface 18 and outside annular surface 20. Cylindrical wall 16 is illustrated r

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as integrally merging at its upper end with annular flange and lip structure comprising an outwardly extending radial directed flange or ring 22 and an inwardly extending radially directed annulus or lip 24. See Figure Ring 22 is illustrated as being sized to be radially flush with the exterior annular edge of the associated cap and comprises seriatum flat bottom surface 26, cylindrical edge surface 28 and top flat surface 30. Adjacent surfaces 26, 28 ."d are illustrated as merging with each other at 90° angles.

Thus, the ring 22 is generally rectangular in cross section.

The interior of the flange lip structure 22 comprises a wide mouth top opening to the hollow interior 38 of the tube through which a liquid specimen, for example, may be introduced and at least part thereof removed after centrifuging or other processing.

The conical bottom of tube 15 comprises a downwardly convergently tapered extension 40 of the wall 16 terminated in a closed lower tip 42. The lower end 40 is conically hollow between the annular merger site 44 with wall 16 and the tip 42.

The interior of the tube 15 is formed in such a way that liquid placed to the same level in several identical containers will comprise the same liquid volume. Graduation markings may be placed upon the exterior surface 20, if desired, to accurately indicate the quantity of liquid existing therein at any point.

-7j Also, the length of the cylindrical wall may be shorter and the lower conical end longer if desired. Any container can be supplied with a writing surface. A writing surface and volume graduations may be formed in the mold at the time the device is injection molded.

Present laboratory technology dictates that the usual volume of a container of the type disclosed herein be within the range of about 0.5 to 2.0 ml. However, the present invention applies to containers of greater or less volume.

As shown in Figures 1-3, cap 17 is joined to its associated cylindrical container 15 by a tether 19. The tether 19 is preferably integrally molded with the associated cap 17 and container 15. The tether 19 is illustrated as being integral with the top region of the cap or lid 17 at site 50 and with the ring 22 of the container at site 52. The tether 19 is illustrated as having a thickness less than one-half of the container lip thickness. The thickness of the tether is to be such as to readily accommodate closing and opening of the lid, yet strong enough to prevent breakage.

The flat tether 19 is comprised of side edges 54 and 56. It is further comprised of top surface 58 and bottom surface (Figure Thp width of thp tpther is illunstrated as being centrally enlarged. When the cap 17 is in the closed position, the strap 19 is folded or looped upon itself, as shown in Figures 1 and 3. On the other hand, when the cap is in the open position, the strap 19 maintains the connection between the cap r i- -a s~ r; aL- a a and container, such that the cap can he positioned in a variety of positions but on no occasion does the cap become separated from the container. Due to the memory of the strap material, the cap 17, when disconnected from the cylinder, tends to return to a linear configuration. See Figure 2.

The strap or tether 19 is shaped to allow the maximum efficiency in hinging capabilities. When the cap is closed, the strap 19 is transversely folded along the approximate midpoint thereof, and the major stress placed upon the strap occurs along this location. Therefore, the middle section of the strap is enlarged in its width to better tolerate the mentioned flexure.

The strap is essentially flat, which also accommodates the stated flexure. Thus formed, the strap provides both a connection and hinging site for the cap 17.

The cap 17 is generally flat across the top thereof, but, as shown in Figure 5, the lower part thereof is essentially frustoconical. More specifically, the cap or lid 17 comprises an exposed top wall 60, which is teardrop-shaped as shown in Figures 1-3. Wall 60 comprises a top exposed flat surface 62 and an underside surface 64 which is stepped at annular diagonal shoulder 66 to integrally merge with annular surface 68, which has an enlarged thickness. Surface 68 is interrupted by an integral reinforcing ring 70. The thin center 60' comprises a membrane or diaphragm for penetration of a hypodermic needle or other piercing instrument.

Li_ The wall 60 also comprises a teardrop-shap-d undersurface.

Teardrop-shaped wall 60 is flanked by a downwardly-directed edge flange wall 172 comprising outside wall surface 176. Surfaces 62 and 172 merge at 900 corner 178. Flange wall 172 is illustrated as being of uniform thickness external of skirt wall 84, extends through the same teardrop configuration as does wall 60 and terminates in lower surface 182. Walls 60 and 172 are integral and transverse to each other and are illustrated as being formed so that surface 176 and surfaces 62 and 182, respectively, intersect at 900 angles.

The flange wall 172 is formed so that when the cap is in the closed position, as illustrated in Figures 1 and 3, the elongated tip 82 of the cap extends beyond the lip 22 of the container to allow the user to easily force the lid 17 upward to open the container. This is accomplished by exerting an upward pressure on the cap at the point where the elongated tip 82 extends beyond the ring 22 of the container. Except for the tip 82, the outer edge surface 176 of the cap is of substantially the same transverse dimensions as surface 28 of the lip 22 of the container A downwardly divergently tapered frusto-conical wall or skirt 84 is located between wall surfaces 184 and 64 and is integral with wall 60. See Figure 5. Wall 84 forms an overall frusto-conical cupular structure comprised of an interior surface an exterior surface 86, and a lower rounded edge 88.

il. 11 I IK- The annular wall 84 of the cup-shaped structure is thicker at site 92 (the juncture point with the cap top wall 60) than it is at the edge 88. The wall, therefore, gently and uniformly convergently tapers from top to bottom. The length of the wall 84 is great enough to form the two annular seals, one where tip 88 contacts surface 18 and the other where ring 24 and surface 86 engage.

The exterior diameter of the wall 84 at the leading edge 88, as well as the exterior diameter beginning at edge 88 and extending along a substantial length of the exterior wall 84, is somewhat greater than the interior diameter of the cylindrical container 15 at surface 18. However, the exterior diameter of the ring at site 92 is less than the interior diameter of the cylindrical container 15 at surface 18.

The walls 60 and 84 form a hollow frusto-conical recess 94 within wall surface Figures 3 and 4 illustrate a presently preferred externallyapplied releasible lock embodying the principles of the present invention. More specifically, the releasible lock, generally designated 110, has a horseshoe configuration and a fore-to-aft length which exceeds the distance from the tip 82 of the cap 17 to the center of the container 15. The interior width of the lock 110, in an unstressed state, is slightly less than the diameter of the container 22.

-11ft i RI~FP ~B ag Ri ~I~I~I i I I Preferably, the lock 110 is formed of polypropylene or another suitable resin, as a single piece using a well known one shot injection molding technique. The polypropylene may be that which is available from Ashland Chemical Company and may be reground polypropylene since the plastic of the lock 110 is at no occasion placed in contact with the liquid specimen contained in the container per se. The horseshoe-shaped lock 110 comprises a top curvilinear flange 112 and lower curvilinear flange 114.

Flanges 112 and 114 are identical, but of opposite hand. Each Flange 112 and 114 is enlarged in the region of the proximal tip 11 5 to better accommodate placement over the tip 82 of the cap 17. The flanges 112 and 114 and the lip edges 116 and 118 preferably accommodate a snug fit when the clip or lock 110 is inserted over the container lid and against the outside surface of the container in the manner illustrated in Figures 9 and Preferably, the inside diameter of the opening created by lip 114 is slightly less than the outside diameter of the container However, the holding engagement can be against the lip 28 of the container or against the wall and lip of the container.

The top and bottom flanges 112 are integrally interconnected by a vertical wall 120, which is illustrated as being of uniform thickness and depth throughout. The wall 120 is integrally contiguous with the one edge each of the flanges 112 and 114.

The thickness of the wall 120 is selected to provide structural integrity and the height is selected so that preferably a snug -12- IL- i I fit is created when the clip or lork 110 is .Inorted upon the container and lid.

This design is particularly intended to accommodate receipt of the projection 82 of the lid 17 in the recess area 122 without compromising the fail safe nature of the lock when fully inserted upon the container and its lid, as illustrated in Figure 4.

As mentioned earlier, the front-to-rear distance of the clip or lock 110 is preferably selected so as to extend beyond the midpoint of the container 15 when fully inserted as illustrated in Figure 10. This, in effect, locks the jaws of the horseshoeshaped lock 110 against inadvertent lateral displacement while creating a fail safe union against rotational displacement of the cap 17 out of its closed and sealed relationship with the upper end of the tube 15. Thus, the end edges 124 and 126 are disposed opposite each other in a common although nonradial plane. The clip or lock 110 may be dimensioned so that when the lock 110 is inserted, upon reaching its fully installed position, the opposed jaws or arms of the clip ending in end edges 124 and 126 close quickly and audibly against the adjacent edge of the lid and container upper lip so that the user is informed by the noise so emitted that the lock 110 is in its fully inserted position. The manual insertion of the lock 110 is accomplished facilely and with minimal manual effort, yet the lid and the container are securely locked one to another by the clip or lock 110 against specimen leakage during centrifuging, freezing, boiling and shipping. By the same token, manual lateral displacement of the -13- L I i lII IBI ~F 1P1 II I i i I lock 110 from its fully installed position of Figure 4 to its removed condition of Figure 3 can be facilely and swiftly accomplished by the user, when the specimen within the container has been fully processed and it is desired by the user to have access to the processed specimen. Furthermore, the injection molded nature of the clip or lock 110 is relatively inexpensive so that it is not necessary for the lock to be reused, although that option is available to the user. Furthermore, the user has the option of choosing to use the lock 110 on all centrifuge containers or only selectively on those which are subjected to extraordinarily high centrifuge stress or hligh risk boiling techniques.

It is to be appreciated that the clip or lock 110 provides a further advantage, i.e. it allows a far greater range of choices in plastics from which the container 15 and its lid 17 may be formed, since maintenance of the closure between the lid and the container is not limited to the union created between those two parts but rather depends primarily and essentially upon the clip or lock 110. Thus, the cost of producing the container 15 and its lid 17 may be reduced by resorting to less expensive plastics, when used with a lock made pursuant to the present invention. Furthermore, it is commonplace for medical technicians and others to write data or indicia upon the exposed surface 62 of the lid 17. The construction of the clip or lock 110 preserves visual observation of any data or indicia so placed upon the surface 62.

-14i Upon removal of the releasible lock 110 from a cap and container having a processed specimen therein, the cap can be manually opened from its interference-fit closed condition. This action sometimes results in displacement or spillage of some of the specimen, risking contamination and inaccuracy in the test results. To avoid such specimen spillage, the present invention contemplates leaving the releasible lock 110 in place after the specimen is has been centrifuged, boiled and the like and drawing the processed specimen through a hole made by a hypodermic needle or other piercing instrument in the diaphragm 60' of the cap 17 just prior to specimen removal. Specimen removal can be via the hypodermic needle when attached to a syringe or by removing the piercing instrument from the hole and passing a micropipette tip through the hole.

Reference is now made to Figure 5 which illustrates a lid or cap, generally designated 17, centrifuge container or vial, generally designated 15 and an O-ring 170. The radiallyextending flange 172 comprises a relatively thick body of material which merges with the upper end of the skirt wall 84.

Flange 172 comprises an annular edge surface 176, the vertical dimension of which is illustrated as being greater than any other vertical dimension of the lid 17. Edge surface 176 merges at rounded corner 178 with top surface 62. Edge surface 176 is essentially perpendicular to surface 62.

i II Surface 176 further merges at corner 180 with a flat bottom surface 182. Surface 182 is parallel to but offset from surface 62, as illustrated in Figure 5, but is comprised of relatively short radial dimension. Surface 182, which is annular, merges with an annular curvilinear groove 184 disposed in the flange 172 adjacent skirt 84. Curvilinear groove 184 merges with the exterior wall surface 86 of the skirt 84. The preferred curvilinear configuration of groove 184 isi circular and is dimensioned to snugly and contiguously receive the O-ring 170 in such an orientation that the O-ring is compressed by tri-surface engagement, as hereinafter more fully explained. The O-ring 170 is presently preferably of molded silicone rubber or polyurethane. The unstressed internal diameter of the seal 170 is less than the transverse dimension shown in Figure 5. In other words, the O-ring is stretched during placement around skirt 84 and remains distended in tension when positioned in groove 184. Thus, the memory of the material forming 0-ring 170 compressively holds the O-ring in the illustrated position.

More specifically, container 15 comprises a relatively thick L-shaped flange 22, which comprises a top flat surface 30, flush and contiguous with the surface 182 and an outside annular edge surface 28, the diameter of which is the same as the diameter of the surface 176, exclusive of lip 82. Thus, surfaces 28 and 176 are vertically flush. Surfaces 30 and 28 merge at corner 196, while surface 30 merges at 900 rounded corner 198 with wall surface 32. Surface 28 merges with bottom exposed surface 195 at -16corner 197. The dimensions of thn slirt 84, the flange 172, the wall 16 above the internal annular ring 24 and the flange 22 are selected so that the O-ring 170 is materially compressed and distorted when the lid 17 is tightly closed upon and secured to the container 15. This results in a significant sealing effect at the 0-ring.

The internal seal 170 can be used in conjunction with the heretofore described externally-applied lock. The placement of lock 110 is illustrated in dotted lines in Figure 5 as having been positioned over the flanges 22 and 172.

The invention may be embodied in other specific forms without department from the spirit or essential characteristics thereof. The present embodiments, are, 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 come within the meaning and range of equivalence of the claims are therefore to be embraced therein.

What is claimed and desired to be secured by Letters Patent is: -17-

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Claims (7)

1. 2. A specimen container according to claim i, wherein the skirt member is configured as a hollow frusto-conical cupular structure which opens into the hollow of the container.
2. 3. A specimen container according to claim 2, wherein the skirt member tapers in thickness from the juncture with the flange to the lower edge.
3. 4. A specimen container according to claim i, wherein the lower edge of the skirt member has an exterior diametbr which is slightly greater that the interior diameter of the tubular container at a point of contact therebetween, thereby causing compression of the resilient skirt member to enhance the sealing contact of the lower edge with the container wall. 0670v/MS 19 A specimen container according to claim 1, further comprising a slightly raised lip ring positioned at the interior wall of the tubular container and near the open proximal end, said ring being located within the tubular container at a position which places said ring in sealing contact with an outer surface of the skirt member without interrupting the seal of the lower edge of the skirt member with the interior wall of the tubular container when the cap is in the closed configuration.
4. 6. A specimen container according to claim 1, wherein the specimen container includes an outward projecting lip extending from the container exterior, said container further including a releasable, externally-applied lock coupled to the cap and container lip and being formed as a one piece structure from a resinous and resilient material, said structure having a first flange configured to restrainingly engage a top rim of the attached cap to prevent cap movement in a direction away from the lip of the container; a second flange configured to restrainingly engage a lower edge of the lip of the container; and connecting structure integrally interconnecting the first and second flanges to form an inwardly oriented receiving channel configured to receive and lock a portion of the top rim of the cap and a bottom edge of the lip of the container in the locked and sealed condition.
5. 7. A method of sealing a specimen within a tubular container having an open proximal end, a closed distal end and an interior wall of straight, noncurving tubular configuration and an exterior lip and cap at or near said proximal open end comprising the steps of: a) imposing sealing means internally between the cap and container to create a seal; b) laterally inserting a resilient, plastic releasable lock jointly enclosing the lip and a top rim of the cap within a receiving channel section of the lock to interlock the cap and lip to retain the seal during processing of the specimen; and wherein said cap formed from i i i a 0670v/MS 20 a resilient polymer material and being releasably engageable with the open proximal end, said cap having a flange portion configured to extend across the proximal end of the container and a male portion coupled to a bottom side of the flange portion and projecting downward such that the male portion extends into the hollow of the container at the open proximal end when in a closed configuration, said container being characterized by said male portion comprising a skirt member formed from a resilient plastic material which divergently tapers from a juncture with the flange portion of the cap, to a lower edge of the skirt member which seals the container by being in direct contact with the straight, noncurving configuration of the interior wall of the container and said sealing means is an O-ring compressed in direct contact between the tubular wall adjacent the open proximal end, (ii) the upper portion of the skirt member and (iii) the flange portion of the cap.
6. 8. A method according to claim 7, further comprising the step of stretching the O-ring over the divergently-shaped skirt member of the cap and compressing the O-ring between the cap, container and skirt member as the cap is closed.
7. 9. A specimen container as substantially herein described and with reference to the accompanying drawings. A method of sealing a specimen within a container as substantially herein described and with reference to the accompanying drawings. S DATED this 23rd day Of December, 1992. MULTI-TECHNOLOGY, INC. By Their Patent Attorneys DAVIES COLLISON CAVE