referring to fig1 there is shown a device 25 known in the art to produce a reversal of flow or communication path when interposed in a section of flexible tubing . the prior art device 25 comprises a hollow , rigid or semi - rigid , u - shaped tube 26 into which a first connector 27 and a second connector 28 have been sealingly attached by means well known in the art . if flexible tubing , such as iv tubing , is cut , and one end is placed over first connector 27 , and the second end is placed over second connector 28 , a reversal , or 180 ° change in the direction of flow occurs . however , such devices have some or all of the problems of the prior art discussed above . first of all , they are hard to form without introducing narrowing of the passageway and attendant problems . as aforementioned , if it is tried to injection mold these devices , an increase in cost is attendant , and a difficult process is needed . additionally , such devices are used in biological fluid processing and since fluid touches the rigid tube 26 , and the connectors ( 27 , 28 ), the choice of materials with which to make these prior art devices are limited , as the adhesive and materials must be biocompatible . in addition , once the biological fluid such as blood or blood products touches the device it may not be reusable , thus increasing the cost per use of such devices . further , failure of such prior art devices will produce non - sterile conditions , resulting in the need to dispose of the biological fluid flowing through the device . additionally , similar types of issues may be encountered in other applications such as ground water or semiconductor applications where prevention of fluid contamination is of concern . in order to solve the problems of the known devices , it was desired to produce a device which was , in preferred embodiments , reusable , less prone to failure , adjustable , which had minimal components , which did not touch the fluid being processed , and a device which could be weight bearing . in order to solve problems of the prior art devices , the improved tubing device 30 shown in fig2 was conceived . the tubing device comprises a support member 31 having a channel 32 formed therein . the curvilinear channel may be such as to reverse the direction of flow or pathway , i . e ., u - shaped , produce a 90 ° in the change of direction of flow , i . e ., “ right angle ” ( or be gradually angled in such a manner to result in a final angle in the flow path of about 90 degrees ), or of any desired shape to perform any desired change in direction , including having linear portions , if desired . the curvilinear channel may be in a single plane or in multiple planes . an opening or aperture 33 may be provided for hanging the support member 31 from a bag hook 34 ( fig1 ) or other such holding device . referring to fig3 , the channel 32 is of a cross - section equal to or less than a semi - circle of a diameter ( dc ) substantially equal to the diameter ( dt ) of the flexible tubing that is to be redirected . when the channel 32 is of this cross - section , the tubing preferably is secured by means well known in the art , such as by adhesive 35 to the channel 32 . since the adhesive or other bonding agent being used contacts only the outside of the flexible tubing 29 , and the surface of the channel 32 , the interior of the tubing is left untouched , thus avoiding problems ( e . g . contamination ) of the prior art involving adhesive on the flow contacting surfaces of the tubing . further , the adhesive prevents the tubing 32 from deforming in a weight bearing situation . with reference to fig4 , an improved tubing device 30 of a construction largely identical to that shown in fig2 is illustrated . the only substantial difference is that the channel 32 provided in a surface of the support member 31 is of a cross - section of slightly larger than a semi - circle of a diameter substantially equal to the flexible tube to be redirected . as shown in fig5 , since the opening of the channel 32 is of a dimension a , smaller than the diameter b of the flexible tubing 29 , the flexible tubing 29 must first be deformed into an oval shape , and then inserted or “ snapped ” into the channel 32 where it is retained because of the shape of the channel 32 . regardless of whether the modification of fig2 or fig4 were used to encase the flexible tubing 29 , one may place two tubing devices 30 in a 180 ° opposed , or “ channels facing ” relationship , and affix them in such relationship . in such configuration , or otherwise , the channels 32 may be of the same or different size or cross - section . in some applications , such as weight bearing applications , it may be desirable to have the orientation of the channel 32 in the support member 31 , at least when it is in substantially a u - shape , such that the legs of the “ u ” face to the right or left , instead of downward . this is because in a weight bearing situation , with a downwardly facing u - shaped configuration , such as shown in fig4 , the flexible tubing 29 at the top of the “ u ” will tend to deform into an oval shape , and thus possibly disengage from , or “ snap - out ” of the channel 32 unless the configuration of the channel 32 is modified at the top of the “ u ” to compensate . additionally , having the “ u ” facing downward can further negatively affect flow characteristics of the fluid through the bend . fig6 shows a modification of the construction shown in fig5 . a two - stage channel 36 is shown in tubing device 30 having a first stage channel 36 a , which may be largely identical to the channel 32 shown in fig5 , and a second stage channel 36 b , which is preferably smaller than the first stage 36 a of the two - stage channel 36 . the second stage channel 36 b would preferably be formed below the first stage channel 36 a , but would operate similarly , i . e ., the cross - section of second stage channel 36 b would be less than , equal to , or slightly larger than a semi - circle of the diameter of the tubing which is desired to be inserted into second stage channel 36 b . if it is desired to use two flexible tubes 29 simultaneously , the modification shown in fig6 a may be used wherein the first stage channel 36 a may be separated completely from the second stage channel 36 b by a slot 39 in support member 31 . the width “ w ” of slot 39 is preferably substantially equal to twice the thickness of the flexible tubing 28 which is to be inserted into slot 39 . this allows the flexible tubing to be suitably deformed ( squeezed together or compressed ) to bring the walls of the flexible tubing 29 together before insertion into slot 39 . after the tubing 29 is deformed and inserted through the slot 39 and into second channel 36 b , it will expand into its proper shape and be held in place . referring now to fig7 and 8 a further modification of the present invention is shown . in the improved tubing device 30 illustrated in fig7 , the channel 32 makes a 90 ° bend , instead of the 180 ° turn illustrated in fig2 . in the improved tubing device 30 illustrated in fig8 , there is a top channel 32 a which makes a 90 ° bend formed in the top surface 31 a of the support member 31 , and bottom channel 32 b , making a 180 ° bend , formed in the bottom surface 31 b of support member 31 . channel ( s ) 32 may be formed in one or more surfaces of a support member 31 , and the shape of the channel ( s ) 32 formed in one of the surfaces of the support member 31 may , or may not be , of the same shape or curvature of channel ( s ) 32 formed in any of the other surfaces of the support member 31 . channel ( s ) 32 may contain linear or other shaped portions as well . with reference to fig9 , there is shown a further modification of the improved tubing device 30 of the present invention which is especially useful in medical devices . in the illustrated embodiment , the channel ( s ) 32 is semi - circular in shape , and the support member 31 is substantially a semi - circular trough 37 containing channel 32 , with suitable spokes or supports 40 helping to keep the shape of the trough 32 . holes or apertures 41 may be provided in the support member 31 to save weight , if desired , and to increase visibility of the flexible tubing 29 . the cross - section of the channel 32 may be more or less than a semi - circle of a diameter of the tubing it is desired to support , as previous described . because of the open construction of the improved tubing device 31 it may easily be hung on a bag hook 34 ( fig1 ) and , therefore , the loop in the flexible tubing 29 , after placement in the curvilinear channel 32 , now becomes weight bearing . since the application of weight to the flexible tubing will tend to deform it , if more than a minimal amount of weight is to be carried , the cross - section of the trough may be of a cross - section of somewhat greater than a semi - circle , for example , two - thirds of a circle . thus the opening through which the tube is inserted is less than the diameter of the flexible tube . or , there may be a lip on the lower edge of the trough . if it is desired to encase the flexible tubing 29 , two of the improved tubing devices 30 having trough 37 may be placed in an 180 ° opposed relationship . fig9 a shows a modification of the construction shown in fig9 which is particularly useful in the weight bearing situations discussed above . since the flexible tubing 29 will tend to flatten out when weight is applied thereto , it is desirable to have a construction that will resist this flattening , as well as prevent the disengagement discussed above . this is accomplished by the improved tubing device 30 shown in fig9 a . there is shown an upwardly facing trough 43 supported by a web 44 . the cross - section of the trough is that of an annular shape of about two - thirds of a circle . therefore , outwardly facing channel 46 has a cross - section of about two - thirds of a circle . when the flexible tube 29 has weight applied , it will try to flatten in a horizontal or lateral direction , and the sidewalls of the tube will try to move sideways . however , they are blocked from doing this by the sidewalls of the radially outwardly facing channel 46 , thus the flexible tube 29 cannot collapse on itself and shut off the flow of fluid being filtered . a hole or aperture 47 is provided in the web 44 for hanging the improved tubing device 31 on a bag hook 34 ( fig1 ). the modifications of the improved tubing device of the present invention , which have been shown thus far , have not completely encased the flexible tubing whose direction is being affected . a further modification of the present invention that does completely encase the flexible tubing is shown in fig1 . this embodiment uses the same principles heretofore described , and has been found to be particularly useful in biological fluid filtration systems , such as that shown in fig1 . for ease of understanding , the modifications of the invention to be described hereinafter will be referred to as a two part improved tubing device and indicated by the numeral 50 although , as will become clear , they can be formed in a single piece with a hinge connecting a first portion and a second portion . although shown with rough or sharp edges for purposes of illustration , it is preferred that smooth and / or rounded edges be incorporated in the tubing devices of the present invention to prevent punctured bags / tubes and packaging . referring specifically to fig1 , the improved two - part tubing device 50 has a first portion 51 and a second portion 52 connected by a hinge 53 , which may be any type of hinge construction well known in the art . first portion 51 of two - part tubing device 50 has a first channel portion or passageway 54 formed therein , while second portion 52 of two - part tubing device 50 has a second channel or passageway 55 formed therein . the first portion 54 and the second portion 55 are placed such that when the first portion 51 of two part tubing device 50 is closed , i . e ., brought into an opposed facing relationship with second portion 52 , the first portion of passageway 54 will be directly opposite the second portion of passageway 55 , and the two together will form a circular or substantially circular channel or passageway 56 ( fig1 ) to capture a flexible tubing 29 whose direction is to be rerouted . the dimensions for the first passageway portion 54 , and second passageway portion 55 and , thus , the diameter of the circular passageway , may be chosen depending on the application . the circular passageway may be slightly smaller than the flexible tubing that is being rerouted such that the tubing is held in slight compression and will not be prone to slippage in the circular passageway or channel 56 formed by first portion 54 and second portion 55 . the provision in the circular passageway or channel 56 of at least one portion 56 a which curves concavely outwardly , and at least one portion 56 b , which curves concavely inwardly , will also help prevent slippage . the shape of the passage way 54 and passage way 55 may not necessarily be the same but complimentary , as it may be preferable to snap the tubing in one side such as first passageway 54 of first portion 51 prior to mating of the two portions 51 and 52 . when closed , first mating surface 57 provided on first portion 51 of two - part tubing device 50 will be in contact with or closely adjacent second mating surface 58 provided on second portion 52 of two - part tubing device 50 . a pair of apertures , openings , or eyes 60 provided in first mating surface 57 will receive a pair of hooks or protrusions 61 provided on second lower surface 58 , which will fixedly , but removably , keep first portion 51 and second portion 52 together to keep two - part tubing device 50 in its closed position . the protrusions 61 may be recessed to prevent sharp edges . in operation the operator would place the flexible tubing into the first portion of channel 54 formed in first portion 51 of two part tubing device , and then close the second portion 52 , or vice versa . when first portion 51 and second portion 52 are brought together and closed , a first central opening 63 provided in first portion 51 will become in mating or opposed contact with second central opening 64 , providing a central opening 66 which may be used to hang the tubing device on a bag hook 34 ( fig1 ), or the like . two - part tubing device 50 has proved particularly useful in biological fluid filtration or dispensing systems . it especially is useful in such biological fluid filtration or gravitational dispensing systems where a loop or elevated portion is used for automating and increasing recovery from a gravitational dispensing of fluid . fig1 illustrates such a system which is disclosed in u . s . pat . no . 6 , 171 , 493 . biological fluid filtration system 70 has a blood container or bag 71 provided upstream from , and elevated above , a leukocyte depletion device 72 . the leukocyte depletion device 72 has an inlet 73 and an outlet 74 separated by a filter media 75 . blood container 71 is connected to , or in fluid communication with said leukocyte depletion device 72 through first conduit 76 . there is also provided a blood - receiving container 78 downstream of the leukocyte depletion device 72 . leukocyte depletion device 72 is connected to blood receiving container 78 through second conduit 79 . an inlet clamp 81 and an outlet clamp 82 may be provided . a bypass line 91 is provided which may be in fluid communication with the blood container 71 and blood receiving container 78 . bypass clamp 84 may be provided in bypass line 91 . in order for the closed loop leukocyte depletion system 70 to work , it is necessary that a “ loop ” 85 of the bypass line 91 be elevated to a sufficient height to prevent the passage of fluid around the leukocyte depletion device . this proved difficult to do in practice until the two part improved tubing device 50 of the present invention was developed . tubing device 50 is shown hanging from a bag hook 34 . the loop portion 85 of the by pass line 91 is positioned such that when the blood container 71 is full of blood , the blood will not reach the loop portion 85 , and thus there can be no flow of blood through the by pass line 91 . the operation of the biological fluid filtration system 70 with the two part tubing device 50 remains identical to that described in applicant &# 39 ; s aforementioned co - pending patent application . a variation on the device shown in fig1 is depicted in fig1 a . this embodiment is very similar to that shown in fig1 except that the flexible tubing 29 is replaced by flexible tubing 29 a , which connects to the top of the blood container 71 as opposed to the bottom of the container 71 , as was depicted in fig1 . this variation can be preferable in certain applications . other than the relocation of tubing 29 a , this embodiment can be substantially identical to that shown in fig1 . flexible tube 29 a is threaded through the tube - holder 50 , which supports the tube and substantially prevents crimping or deformation of the tube 29 a . referring to fig1 the construction of fig1 is shown in its closed position . the clamp portion 87 of the two - part tubing device 50 can be clearly seen in fig1 . clamp portion 87 takes the form of an upstanding wall 88 which extends substantially vertically from first portion 51 of the two part tubing device 50 . upstanding wall 87 has a tubing opening 89 of a predetermined desired size such that flexible tubing 29 can pass therethrough , and a clamp opening 90 having a wider portion 86 into which tubing can pass through easily , and a narrowed portion 92 having a width essentially twice that of , or perhaps slightly less , than the wall thickness of the flexible tubing 29 , such that when the tubing is moved from the wider portion 86 of the clamp opening 90 into the narrowed portion 92 the walls of the flexible tubing 29 are essentially pushed together and brought into contact , thereby cutting off the fluid flow through the tubing that is in the clamp opening 90 . the construction shown in fig1 and 15 is in large part similar to the construction shown in fig1 and 13 . the only substantial difference between the constructions is the fact that the first portion 51 and second portion 52 of the improved two part tubing device 50 have been modified so that the first portion 54 , and the second portion 55 of the circular channel 56 are shaped so as to change the flexible tubing by making a 90 ° bend in the same instead of a 180 ° bend . in addition , there are multiple clamp portions 87 , one extending from each side of the two - piece tubing device 50 . similarly , the construction shown fig1 and 17 is substantially identical to that shown in fig1 and 15 , except that the first portion 51 and the second portion 52 of the improved two piece tubing device 50 have been modified to provide for changing the direction of the tubing for 135 ° rather than the 90 ° shown in fig1 and 15 . referring to fig1 and 19 , there is shown a further modification of the two - piece tubing device 50 previously illustrated . for clarity of understanding , this device is referred to as a multi - path two - piece tubing device , and indicated by the numeral 95 . in this construction the first portion 51 and the second portion 52 of the multi - path two - piece tubing device 95 still have the first portion 54 and the second portion 55 of the curvilinear channel or passageway formed therein . however , the circular passageway 51 formed by the combination of the first portion 54 and the second portion 55 no longer has a single inlet and a single outlet , but rather one possible inlet point indicated by the numeral 97 , and multiple outlet points , such as first branch 98 , second branch 99 , and third branch 100 to provide for a change in direction of the flexible tubing by 90 °, 135 °, and 180 ° respectively . the remainder of the construction stays substantially the same . referring now to fig2 and 21 , the use of our improved two part tubing device is shown in a biological fluid filtration system similar in part to that illustrated in fig1 but requiring a first tubing loop 101 and a second tubing loop 102 , both formed using the improved two part tubing device 50 of the present invention . clearly the multi - path two portion tubing device 95 just described could also be used . in this modification , not only is flexible tubing 29 held in the passageway created within the first portion 51 and second portion 52 of the two part tubing device 50 , but the first conduit 76 providing fluid communication between the blood bag 71 and the leukocyte filtration device 72 passes through the tubing opening 89 and a second flexible tubing 105 passes through the clamp opening 90 , and can be clamped and unclamped as desired , resulting in the need for one less tubing clamp for the operation of the system illustrated . the use of multiple tubes traveling in multiple paths is well within the scope of the present invention . referring now to fig2 and 23 , there is shown a further modification of the improved tubing device 30 embodying the present invention , and having a flexible support member 31 a having at least one , and preferably a pair of channels 32 , formed proximate the ends thereof . flexible tubing 29 will pass through the channels 32 and form a u shape above the flexible support member 31 a . the flexible support member may hang on a hook for support . depending on the application , channels 32 may be of a diameter slightly less than , substantially equal to , or slightly larger than , the diameter of the flexible tubing 29 . if adjustability is highly desired , it would be preferred to make the channels 32 larger than the tubing 29 . if the channels 32 are smaller than the tubing 29 , there would be substantially no adjustability . if the channels 32 are substantially the same , the position of the tubing 29 will be adjustable , when desired . a first leg 29 a of the tubing 29 leg needs to be pulled , while the second leg 29 b of the tubing 29 is pushed to adjust the length of each leg position of the loop . these same considerations as to the size of the channel 32 in relationship to the size of the tubing 29 will apply to any embodiment of the invention where at least a portion of the tubing 29 is encased , surrounded or encircled by at least one , and preferably two channels 29 , such as shown , by way of example and not of limitation , in fig1 - 21 . referring now to fig2 , a modification of the present invention is shown comprising a rigid or semi - rigid support member 31 b , having a hole or aperture 30 a therein by which the support member 31 b may be hung by a hook or other well known support means . a pair of channels 32 are provided in predetermined desired positions in support member 31 b , and flexible tubing 29 is passed through channels 32 to form a u shaped ( upright or inverted ) loop . the size of the channels with respect to the tubing will be chosen as discussed hereinabove , depending on the degree of adjustability desired . thus , by carefully considering the problems in the art , a novel tubing device to capture and redirect flexible tubing , while at the same time to enable it to be weight bearing , has been provided .
an improved tubing device , preferably for use in the medical industry is provided . the tubing device provides a seamless transport path by using the tubing itself as the transport means without any other internally wetted parts , or connections , to provide a substantial reduction in the number of fluid contact components , and eliminate the need for cutting tubes into segments to be later bonded via tubing connectors . this can reduce the risk of contamination of the transported materials and can also reduce the use of chemicals such as adhesives and bonding agents .