GB2134789A

GB2134789A - Adjustable length tube and seal therefor

Info

Publication number: GB2134789A
Application number: GB08303868A
Authority: GB
Inventors: David Edward Cross
Original assignee: Bard Ltd
Current assignee: Bard Ltd
Priority date: 1983-02-11
Filing date: 1983-02-11
Publication date: 1984-08-22
Also published as: GB8303868D0; FR2540964A1; SE8400687L; SE8400687D0; JPS59155262A; DE3403874A1

Abstract

An assembly is disclosed of a container (10) e.g. a urine bag to be worn by a patient and a tube (13) having at its end remote from the container a connector (15) and the length of the tube between the connector and the container (10) being capable of extension from a compact disposition, as shown, to a fully extended disposition (E). Tube (13) is formed with a series of ring corrugations (23) any number of which can be "flipped" as required from a compact to an extended disposition to set the required length of the tube. In a second embodiment (Fig. 2) the tube is slidable within a collar. Figs. 3-9 give details of sealing arrangements between tube and collar. <IMAGE>

Description

SPECIFICATION Adjustable length tube and seal therefor This invention relates to an adjustable length tube and, more particularly, but not exclusively, concerns an assembly of a sterile container for bodily fluid and a connecting tube for flow of fluid into the container.

There are a number of medical conditions which require a patient to wear a sterile urine bag on his or her leg, or to remain connected to a sterile urine bag when resting in bed. It will be appreciated that there is no one single length of input tube with which such a bag can be provided which will satisfy all patients. For example, it is common for female patients to wear a leg bag strapped to their thigh, and for male patients to wear a leg bag strapped to their lower leg.

It has been suggested to provide a urine leg bag with an inet tube long enough to satisfy all users, and provide a removable connector on the distal end of the tube so that a user may remove the connector, cut the inlet tube to the required, shorter length and re-attach the connector. It is, however, a disadvantage of such a proposal that the interior of the bag may become contaminated with organisms foreign to those of the bag user, with consequent danger to the patient.

It is one object of the present invention to provide a urine leg bag with an inlet tube whose length can be adjusted without risk of such contamination.

According to a first aspect of the present invention there is provided an assembly of a tube of circular or near circular cross section and a sealing component which forms a seal around the external surface of the tube for permitting telescopic movement of the tube in the sealing component in at least one direction, characterised in that the tube is made of a flexible synthetic polymeric material, and in that the sealing component is a collar the inside surface of which includes an outstanding sealing ring located intermediate the ends of the collar for sealing engagement with the external surface of the tube, and the bore diameter of the collar increases from the sealing ring to each end of the collar.

Preferably the collar is made of a rigid or semirigid synthetic polymeric material such as an acetyl or acrylic plastics material or NYLON and is set into the top edge of a urine leg bag. The inlet tube of the leg bag, within the collar and in sealing engagement with the sealing ring thereof, is also preferably of PVC material.

As supplied to a user, the leg bag has its inlet tube withdrawn as far as possible into the interior of the leg bag, and when the user prepares the bag for use he pulls the inlet tube through the collar outwardly of the bag, by as great a distance as he requires for his particular convenience.

It will be appreciated that this pulling movement will have the effect of putting the material of the inlet tube between the sealing ring of the collar and the grip of the user in tension so that the diameter of the tube will tend to become slightly smaller than when the tube is not under tension. This reduction in diameter will facilitate movement of the inlet tube through the collar.

Conversely, it will be much more difficult, and could be made practically impossible, for the user I to push the inlet tube back into the interior of the leg bag. This has the advantage of effectively sealing off the interior of the bag from external contamination.

It is usual to provide the outlet end of the inlet tube of a leg bag with a non-return valve. In the above described bag according to the invention, it is convenient to provide a non-return valve in an end fitting attached to the outlet end of the inlet tube and which is of greater diameter than the tube in order to prevent it being withdrawn completely out of the bag through the sealing collar. The end fitting can be provided with an outward facing seating surface and a resilient disc with an almost complete annular cut-out of greater diameter than the seating surface which is pushed downwardly, away from the seating surface, by flow of urine through the inlet tube but which returns after cessation of such flow to seat on the seating surface and provide the required non-return valve function.Otherwise, the non return valve could be provided by a ball valve or a "lay flat" valve as is fitted on urine leg bags currently sold by the present Applicant.

For even greater security against the possibility of re-entry of a contaminated length of the inlet tube into the interior of the leg bag, a flexible gaiter can be provided over that portion of the length of the inlet tube which can move from a position external of the sealing ring of the collar to the other side of the sealing ring, inside the bag.

The present Applicants, having realised that it is a practical possibility to provide means for adjusting the length of the inlet tube of a sterile leg bag for urine, are now able to visualise embodiments of the invention which work on a quite different principle.

According to a second aspect of the present invention, therefore, there is provided an assembly of a container for bodily fluid, the interior of which has been rendered sterile, and a connecting tube through which the fluid flows, in use of the assembly, into the container, the connecting tube having at its distal end a connector for connecting the tube to a fluid flow member upstream of the assembly, and the straight line length of the tube between the connector and the junction between the tube and the container being capable of extension from a compact disposition, through a plurality of stable, intermediate length dispositions, to a stable, fully extended disposition.

In one embodiment of the second aspect of the invention, a sterile urine leg bag has an inlet tube which incorporates an extended series of corrugations such as can be found on certain drinking straws of synthetic polymeric material which can be bent, in the area of the corrugations, to take up a stable, bent disposition, by "flipping" on the outside only of the bend of whatever number of the individual corrugations is required in order to give the required bend angle.While the property of such a corrugated tube, to take up a particular bend angle, may well be useful in embodiments of the present invention, for example to shape the inlet tube around the surface shape of the limb of a patient, the particular property of the corrugated tube which is required is the ability of individual corrugations to "flip" around the entire circumference of the inlet tube, rather than just on the outside of a bend. Thus, the length of the inlet tube is adjustable from a compact disposition in which all of the corrugations are "doubled back on themselves" to a fully extended disposition in which all of the corrugations are opened out, through a plurality of intermediate length dispositions where only some but not all of the corrugations have flipped from the doubled back to the opened out configuration.

Corrugated tubes of the type referred to above are available from Sweetheart International Limited, of Gosport, Hampshire, England.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a view from one side of a first embodiment of leg bag according to the invention, with an inlet tube and associated components of the bag shown in section; Figure 2 is a similar view of a second embodiment of leg bag; Figure 3 is a detail of Figure 2, showing a collar in section with an inlet tube sealing ring, and part of the inlet tube so sealed; Figure 4 is a fragment of Figure 2 showing the sealing ring in more detail; Figure 5 shows a modified collar in section; Figure 6 shows in more detail the Figure 5 sealing ring; Figures 7, 8 and 9 show in section three alternative collar and sealing ring constructions.

In Figure 1 there is shown a sterile leg bag 10 of a construction which in many respects is conventional. It has a welded top edge 11 in which is captivated a sleeve 12 for receiving an inlet tube 13 on the distal end 14 of which is mounted a connector 15 for engagement with a urine drainage member such as a catheter worn by a patient. The bag itself is fastened to the patient's leg by straps fitted to apertures 16 in the welded side seams 17 of the bag. In the bottom seam 18 of the bag is captivated the upstream end of a drain valve 19, and at the lower edge of the sleeve 12 is a "lay flat" non-return valve 20 which comprises a thin-walled short tube of plastics material which is creased at its side edges 21 so that it lies flat within the bag 10, the two flat faces of the valve moving apart only when there is flow of urine into the bag from the inlet tube 13.

The inlet tube 13 includes a section 22 where the wall of the tube 13 is corrugated. Each corrugation 23 can "flip" between a compact disposition where both "sides" of the corrugation slope away from the longitudinal axis of the inlet tube on the same side of a plane transverse to the length of the tube, and an extended disposition in which the two sides of the corrugation extend away from the axis on opposite sides of the plane, the transition being accomplished by endwise tension on the tube causing the side of the corrugation more nearly parallel with the transverse plane moving through an unstable, stressed configuration where it is parallel with the transverse plane.

More or less endwise tension will cause the required number of corrugations to "flip". In Figure 1 only one corrugation 24 has flipped. If endwise tension were to be maintained until all had flipped, the connector 15 would be at the fully extended disposition E shown chain dotted. If the corrugation 24 were to be returned to its compact disposition, by endwise compression of the tube, the distance between the connector 15 and the bag 10 would be slightly shorter than shown, and the tube in a fully compact disposition.

The "corrugation flipping" effect has previously been proposed, as mentioned above, for drinking straws, and certain materials of a composition as used for such straws can be used for the inlet tubes.

The inlet tube 13 is secured at its distal end to the connector 15 and at its other end to a sleeve insert 25 which has a lip 26 for engagement with the lower end edge of the sleeve 12 to prevent removal of the insert 25 from the bag.

In the bag of Figure 2 most of the components are identical with those of Figure 1 and are identified by the same reference numerals.

However, the fitting 30 in the top edge 11 is different, as will be explained further below. The inlet tube 31 is a plain PVC tube which is fitted in polymeric collar 33 in sealing engagement therewith. The collar 33 is itself fitted within a PVC sleeve 35 bonded into the top edge of the bag 10, so that the whole fitting 30 is fluid-tight.

The collar 33 has a lip 36 at its lower end and a shoulder 37 at its upper end and these locate it within the sleeve 35 and prevent its withdrawal from the sleeve. The collar 33 is fitted into the sleeve by driving the lipped lower end down through the sleeve 35 with elastic deformation of the sleeve.

The inlet tube 31 slides in the collar 33 between a compact disposition C as shown, in which a considerable part of the length of the tube 31 is within the bag 10, to an extended disposition E, again shown chain dotted. A limit to extension of the inlet tube is provided by abutment of an enlarged inlet tube end cap 32 with the lower edge of the collar 33. The cap 32 carries a non-return valve which may be, for example, a ball valve or utilize a valve member with an incomplete annulus, as mentioned above.

The collar 40 shown in Figure 3 and the collar 50 of Figure 5 are suitable for use in the fitting 30 shown in Figure 2. It will usually be convenient to provide the sleeves 40 and 50 with a lip 47 at their lower end and a shoulder 48 at their upper end, as shown, to secure them in the sleeve 34 in the same manner as the insert 25 is held in the sleeve 12 and the collar 33 is held in the sleeve 35.

Referring to Figures 3 and 4, the collar 40 has an inwardly projecting ring 41 with a flat end face 42 parallel with the length of the sleeve and flanked by flat banks 43 and 44 at 450 to the collar length. Beyond the bank 43, the tube bore slopes at an angle of 20 to the length of the tube, all the way to the top end 45 of the collar, which is the end external of the bag 10 in use. Beyond the bank 44 the bore has a corresponding slope to the lower, inner end 46 of the collar 40 of 1 O. The difference of radius of the bore of the collar between the top and the bottom of both of the banks 43 and 44 is 0.15 mm. The length of the flat seal face 42 is 0.3 mm.

The collar 50 of Figures 5 and 6 is similar, except that the bank 53 is flanked by a flat zone 57 in which the bore of the collar 50 is cylindrical, and a like flat zone 58 lies adjacent the bank 54.

Between the flat zones 57 and 58 and the respective ends 55 and 56 of the collar 50 the bore slopes as in Figure 4.

As seen in Figures 3 and 5, the diameters of the inlet tube 30 and the bore of the collar are chosen so that the inlet tube is nipped in at the sealing ring. The tube 30 is readily pulled through the collar but it is very difficult, and not practicable, to push the tube through, as explained above. Thus, in use of the bag, the patient pulls out the inlet tube 30 to the required length, being careful not to pull the tube too far. Conversely, with the Figure 1 embodiment it may be relatively easy to shorten the tube, if it has been lengthened too much, by flipping into the compact disposition as many of the extended corrugations 34 as necessary.

The construction and operation of the alternative, but less preferred, collar constructions shown in Figures 7, 8 and 9 will be largely apparent from the drawings, without detailed explanation. Thus, the collar 60 of Figure 7 has several wiper rings 61 and could be made from a semi-rigid, synthetic polymeric material, the collar 70 of Figure 8 carries a pair of O-ring sealing rings 71 and the collar 80 of Figure 9 comprises two end mouldings 81 and 82 solvent or heat welded to a common intermediate member 83 to captivate two O-ring seals 84.

In the manufacture of PVC tubes, it cannot be guaranteed that the tubes, when relaxed, are always perfectly circular. The use of a rigid or semi-rigid polymeric collar in which a PVC tube slides telescopically is believed by the Applicant to represent a new sealing principle of major use in a wide variety of applications where a flexible tube of adjustable length, not necessarily of PVC, is required. The required collars could be fabricated by use of injection moulding technology, and the problem of the undercut of the tooling, associated withthe sealing ring and bore slope, could be overcome by, for example, relying on the elastic properties of the collar material to "bump" the formed collar off the tool, or by forming the tool in two halves which mate at the sealing ring.

Claims

1. An assembly of a container for bodily fluid, the interior of which has been rendered sterile, and a connecting tube through which the fluid flows, in use of the assembly, into the container, the connecting tube having at its end remote from the container a connector for connecting the tube to a fluid flow member upstream of the assembly, and the straight line length of the tube between the connector and the junction between the tube and-the container being capable of extension from a compact disposition, through a plurality of stable, intermediate length dispositions, to a stable, fully extended disposition.

2. An assembly as claimed in claim 1, wherein the container is a urine drainage bag.

3. An assembly as claimed in claim 1 or 2, including means for fastening the container to the body of a user.

4. An assembly as claimed in claim 3, wherein the fastening means is for fastening the container to a leg of the user.

5. An assembly as claimed in any one of the preceding claims wherein the inlet tube incorporates a plurality of corrugations, each in the form of a ring, the plurality forming a series of the rings along at least a portion of the length of the inlet tube, each one corrugation being movable between two stable dispositions, namely, a compact disposition and an extended disposition in which the length of the one corrugation, in the direction of the length of the inlet tube, is greater than when the corrugation is in the compact disposition, whereby any desired length of the inlet tube intermediate between a compact disposition (in which all the corrugations are compact) and a fully extended disposition (in which all the corrugations are extended) is provided by moving an appropriate proportion only of the corrugations to be in the extended disposition.

6. An assembly as claimed in any one of claims 1 to 4, wherein the inlet tube is of circular or near circular cross-section and is telescopically slidable within a collar in the periphery of the container, there being a sealing co-operation between the tube and the collar.

7. An assembly as claimed in claim 6, wherein the inlet tube is made of a synthetic polymeric material.

8. An assembly as claimed in claim 7, wherein the tube is made of polyvinylchloride.

9. An assembly as claimed in claim 6, 7 or 8, wherein the collar has on its inward-facing, sealing surface an annular sealing zone intermediate the ends of the collar at which is the sealing co-operation with the external surface of the inlet tube.

10. An assembly as claimed in claim 9, wherein the sealing zone comprises an outstanding sealing ring which is unitary with the collar itself.

11. An assembly as claimed in claim 9 or 10, wherein the inside diameter of the collar increases from each end of the sealing zone to the adjacent end of the collar.

12. An assembly as claimed in any one of claims 6 to 11, wherein the sealing co-operation is such that the tube is placed in radial compression within the collar.

13. An assembly as claimed in any one of claims 6 to 12, wherein the collar is made of a rigid or semi-rigid synthetic polymeric material.

14. An assembly as claimed in any one of claims 6 to 13, wherein the inlet tube has at its end within the container an enlarged diameter formation which prevents said end being pulled through the collar.

15. An assembly as claimed in claim 14, wherein the enlarged diameter formation comprises a non-return valve.

16. An assembly as claimed in any one of claims 6 to 15 comprising a sleeve which is disposed within the periphery of the container and itself receives the said collar.

17. An assembly as claimed in claim 16, wherein the sleeve is elastically deformable to receive the collar.

18. An assembly as claimed in claim 17, wherein the collar is retained within the sleeve by engagement of co-operating retaining surfaces on the sleeve and the collar.

19. An assembly as claimed in claim 18, wherein the retaining surfaces comprise a radially outwardly extending lip, at the end of the collar which in use is on the interior of the periphery of the container, and a shoulder at the other end of the collar, the lip and shoulder co-operating with the opposite end surfaces of the sleeve, and the sleeve being sufficiently resilient to allow passage through it of the lip.

20. An assembly of a tube of circular or near circular cross section and a sealing component which forms a seal around the external surface of the tube for permitting telescopic movement of the tube in the sealing component in at least one direction, characterised in that the tube is made of a flexible synthetic polymeric material, and in that the sealing component is a collar the inside surface of which includes an outstanding sealing ring located intermediate the ends of the collar for sealing engagement with the external surface of the tube, and the bore diameter of the collar increases from the sealing ring to each end of the collar.

21. An assembly of a container for bodily fluid and a connecting tube substantially as hereinbefore described with reference to, and as shown in, Figure 1 of the accompanying drawings.

22. An assembly of a container for bodily fluid and a connecting tube substantially as hereinbefore described with reference to, and as shown in, any one of Figures 2 to 9 of the accompanying drawings.