Selectively detachable apparatus

Abstract

Organoplastic apparatus which is capable of being frangibly separated into a plurality of individual segments. The separable segments are attached to one another by a relatively thin narrow frangible member which is integral with and extends longitudinally between the separable segments. This frangible member is reinforced by at least one integral rib member which extends transversely thereof between the separable segments.

Description

BACKGROUND AND PRIOR ART

Organoplastic laboratory apparatus having a plurality of chambers or test wells is well-known. Usually such apparatus is used in the form in which produced, and the user selects an apparatus having the desired final number of chambers or test wells. The manufacturer can make available several forms of a particular type of apparatus each form having a different number of chambers or test wells. This increases the unit manufacturing cost and still limits the user to the particular apparatus configurations supplied by the manufacturers.

It has been suggested in the prior art that a multiple chamber apparatus be provided which is separable into segments each having a lesser number of chambers than in the initial overall apparatus. It was previously suggested that the spacing between adjacent chambers could be scored, as with a glass cutter, the chambers to be separated by breaking the apparatus along the scored line. This technique is expensive from a manufacturing standpoint. Another prior art suggestion was to form the apparatus with a thin frangible member between adjacent chambers, such member to be broken by bending. This technique had the disadvantage of requiring several bending movements in order to break the frangible member.

There is thus a need for organoplastic apparatus which can be inexpensively manufactured and which, with a minimum of effort, can be separated as desired into segments.

SUMMARY OF THE INVENTION

In accordance with the present invention unitary organoplastic apparatus is provided which is capable of being frangibly separated into a plurality of individual segments wherein the separable segments are attached to one another by a relatively thin narrow frangible member which is integral with and extends longitudinally between such separable segments, each thin frangible member being reinforced by at least one integral rib member which extends transversely thereof between the separable segments.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the present invention;

FIG. 2 is an enlarged vertical cross-section view taken along Line 2--2 of FIG. 1;

FIG. 3 is an enlarged vertical cross-section view taken along Line 3--3 of FIG. 1;

FIG. 4 is a vertical cross-section view taken along Line 4--4 of FIG. 2;

FIG/ 5 is a plan view of the underside of another embodiment of the present invention; and

FIG. 6 is an enlarged partial lower perspective view of the underside shown in FIG. 5.

DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 and 2, the illustrated embodiment of the apparatus 10 of the present invention comprises an elongated rectangular base portion 12 having a planar top surface 14, a planar bottom surface 15 and a plurality of walls, such as 16 and 18, extending upward from said base portion to form a plurality of spaced rectangular chambers or test wells. Walls 16 form chamber 17 and walls 18 form adjacent chamber 19. In a similar fashion chambers 20, 21, 22, 23, 24 and 25 are formed on said base portion. Formed in the bottom surface 15 is a longitudinal groove 26 which separates the base portion 12 into two elongated segments 27 and 28 which are attached to each other by an elongated thin narrow member 29 which is integral with and extends longitudinally between such segments. This thin member 29 is reinforced near one end by an integral rib member 30 which extends transversely thereof between segments 27 and 28. The member 29 is reinforced near its other end with a similar integral rib member 31 which is shown in FIG. 2.

Apparatus 10 is easily and inexpensively formed as a unitary structure from frangible organoplastic materials, such as polystyrene, polyacrylate, polymethacryate, acrylonitrile-styrene copolymers, nitrile-acrylonitrile-styrene copolymers, polyphenyleneoxide, phenoxy resins and the like. These materials are also desirably transparent.

The apparatus illustrated in FIG. 1 has eight chambers or test wells. If it is desired to employ only four chambers, segment 27 which has the desired number of chambers can be detached from segment 28 by breaking the apparatus along thin narrow frangible member 29. When forces are applied to the apparatus, as shown by the arrows labeled "F" in FIG. 4, which tend to bend the two segments 27 and 28 about a hinge formed by member 29, the rib member 30 prevents such bending and forces member 29 to conveniently break due to tensile stress. If rib member 30 were not present, member 29 would just bend and would require several back-and-forth bending movements before member 29 would break. The presence of rib member 30 thus enables the two segments to be separated easier than if it were not present. In view of the extended length of thin narrow frangible member 29, it is desirable to have additional rib members, such as rib member 31, disposed along its length to assist in preventing appreciable bending of member 29.

If it is desired to have the apparatus separable into still smaller segments, the structure of the embodiment shown in FIG. 5 can be employed. Elements in FIG. 5 corresponding to similar elements in FIGS. 1-4 have the same numbers with the suffix a. As shown in FIG. 5, the bottom surface 15a of base member 12a is formed with transverse grooves 32, 33, 34 and 47 as well as with longitudinal groove 26a. The transverse grooves enable the segments to be broken off along the corresponding thin narrow frangible members 35, 36, 37 and 46. Rib members 38 and 41 reinforce the frangible member 35, rib members 39 and 42 reinforce the frangible member 36, rib members 40 and 43 reinforce the frangible member 37 and rib members 44 and 45 reinforce the frangible member 46 in the same way that rib members 30a and 31a reinforce the frangible member 29a. Rib members 38, 39, 40, 41, 42, 43, 44 and 45 function as described above to prevent bending of the thin narrow frangible members reinforced thereby during breaking. There must be at least one rib member associated with each thin narrow frangible member that is to be broken.

Further details of the relationship between the grooves and the rib members of FIG. 5 are shown in FIG. 6. This is an enlarged partial lower perspective view of the underside shown in FIG. 5. The various elements corresponding to those of FIG. 5 are numbered identically.

The frangible member, such as element 29, should have a thickness of about twenty percent of the thickness of the adjacent members, such as element segments 27 and 28. The width of element 29, for example, between segments 27 and 28 should be about equal to its thickness. The rib member, such as rib 30, should have a width about equal to that of the thickness of the frangible member 29 and a depth at least about equal to the width of the rib member.

The thin frangible member shown as element 29 in FIG. 4 has a thickness, measured in the dimension "X", of from about 0.01 to about 0.015 in. and a width from segment 27 to segment 28 of from about 0.01 to about 0.015 in. when segments 27 and 28 have a thickness of about 0.05 in. The rib members represented by element 30 in FIG. 4 and element 30a in FIG. 5 have a width, measured in the dimension "W", of about 0.015 in. and a depth distance, measured in the dimension "Y", of from about 0.015 to about 0.045 in.

The above-described apparatus employed a total of eight chambers or test wells. It is understood that apparatus of the present invention can employ more or less than eight chambers or test wells.

The apparatus of the present invention is useful in a well-known manner in medical laboratory practice as well as in biological research to grow various cells or tissues in particular media.

Claims

What is claimed is:

1. An organoplastic device having a plurality of test wells for receiving material, the test wells being formed on a generally planar base, the base having a top and a bottom surface, and having at least one straight groove extending edge to edge in the bottom surface and extending toward the upper surface, each said groove providing a locus for frangible separation of the formed test wells, the residue above each said groove constituting a frangible member for the said separation, each frangible member being reinforced by at least one solid rib member transverse to the respective groove within the groove and dependently contacting the upper portion of the groove, the total thickness of said rib member and said frangible member being less than the thickness of said generally planar base.

2. Apparatus according to claim 1 wherein the organoplastic material is selected from the class consisting of polystyrene, polyacrylate, polymethacrylate, acrylonitrile-styrene copolymers, nitrile-acrylonitrile-styrene copolymers, polyphenyleneoxide and phenoxy resins.

3. Apparatus according to claim 1 wherein the frangible member has a thickness of about 20 percent of the thickness of the generally planar base and a width about equal to its thickness and wherein the integral rib member has a width about equal to the thickness of the frangible member and a depth at least about equal to the width of said rib member.

4. Apparatus according to claim 1 wherein the frangible member has a thickness of from about 0.01 to about 0.015 in. and a width of from about 0.01 to about 0.015 in.

5. Apparatus according to claim 1 wherein the reinforcing rib member has a width of about 0.015 in. and a depth of from about 0.015 to about 0.045 in.