GB2131511A - Swivel coupling - Google Patents

Abstract

A three part swivel connector is made of concentrically arranged tubular male 12 and female 10 members with a collar 44 interposed around the male element at the entrance to the female member to enclose an O-ring seal 42 against a shoulder 40 to provide a liquid seal in a swivel connector for use with a catheter. The device can be easily manufactured with the collar cemented in place to provide an inexpensive throw-away swivel connector assembly. <IMAGE>

Description

SPECIFICATION Swivel coupling Technical Field This invention relates to connectors for tubing associated with a catheter and more particularly to a swivel connector adapted to be inserted in a fluid line between the fluid source and the catheter. The device is designed for swiveling action so that the catheter may be freely rotated during insertion into a blood vessel, for example, without there being any inhibition of the swiveling action by reason of one end of the connector being attached to a relatively non-rotatable fluid supply means.

Background Art PriorArt Statement Swiveling type connectors adapted for use in various fluid distributing systems are shown in the following U.S. Patents: 2,542,701 to Press, Feb. 20, 1951; 2,560,263 to Wiegand et al., July 10, 1951; 2,570,406 to Troshkin et al., Oct. 9, 1951; 2,893,395 to Buck, July 7, 1959; 2,963,304 to Comlossy Jr. et al., Dec. 6, 1 960; 3,372,948 to Arneson, Mar. 12, 1968; 3,394,954 to Sarns, July 30, 1968; 3,503,385 to Stevens, Mar.31, 1970; 3,768,476 to Raitto, Oct. 30, 1 973; 3,785,683 to Adelhed, Jan. 1 5, 1974; 3,799,589 to Boelkins, Mar. 26, 1974; 3,957,293 to Rodgers, May 1 8, 1 976; 4,152,017 to Abramson, May 1, 1979; 4,253,684 to Talbert et al., Mar. 3, 1981; and 4,254,773 toWaldbillig, Mar. 10,1981.

Referring to the patents mentioned above 2,542,701; 2,560,263; 2,570,406; 2,963,304; 3,372,948; 3,799,589; and 3,957,293 relate to relatively heavy duty industrial fluid coupling means usually fabricated of metal parts adapted to be threadedly engaged. While they do show swiveling connector means, these devices are usually more complicated structures including in some instances ball bearings, which because of these complications would interfere with their utility in the more demanding medical catheter field of use in a hospital to which the present invention is directed.

Patents 2,893,395; 3,503,385; 3,768,476; 3,785,683; and 4,253,684 show quick connecting fluid conduit means for use in medical or more delicate laboratory situations, which connectors are designed especially to be rotatable or inherently show such an ability. Of this group of prior art references all but 3,768,476 and 4,253,684 show multipart connecting means which in a hospital setting would present problems with respect to sterilization and assembly or cost of manufacture. 3,768,476 discloses a coupling made of plastic elements but shows a design having enclosed cylindrical coupling means that would present problems with clean up and therefore would be difficult to sterilize as well as present problems in the manufacture thereof. 4,253,684 in Fig. 6 shows a snap fit type of connector.This disclosure is primarily concerned with forcing sterile air to flow over the mouth of the connector when a tube is being connected thereto. While the particular connection between the blowing element and the tube might be rotatable, it appears that a substantial friction fit would be required to retain the tube in the blowing element, which fit would interfere with a completely free rotation of the tube with respect to the connector.

More typical swiveling catheter connectors or the like are shown in the following patents: 3,394,954 shows a connector designed for medical appliances having a quick connect or disconnect ability. Two cylindrical elements are provided adapted to be slid together axially so that an integral cantilever type spring latches onto the male element extending over the telescopically interfitted end of the female member to engage over a shoulder surrounding the female element to hold the assembly together. This produces a relatively elongated structure having an integral snap connector latch means difficult to manufacture in quantity with any great degree of precision.

4,152,017 describes a specialized connector for a tube to be inserted into the trachea. The connector is designed to swivel and includes a male and female pair adapted for telescopic interfitting and having an interference fit to hold the pair assembled. To accomplish this at least one of the elements must be made of a deformable soft plastic. The snap fit design here shown made of two dissimilar materials results in a permanent assembly which would make it more difficult to clean and sterilize after use.

4,254,773 also shows a snap fit locking design for holding the male and female elements of a swiveling connector assembly. Such a connector requires some resilience in the snap fit design and this suggests that the female member which supports the latching means must be made of a softer or somewhat resilient material to permit the necessary deformation during assembly.

Disclosure of the Invention In recent years great advances have been made in the study of the heart and other organs. New operations have been perfected to replace certain defective parts of the heart, as well as remove and replace certain individual organs or blood vessels connected with a particular affected area of the anatomy. One of the techniques sometimes used by surgeons in this work involves the insertion of a catheter into the vascular system for delivery of fluids thereto, for example dye solutions, that work through the affected organ as a series of X-rays or other studies are made, to pinpoint the exact type of defect thought to be present and attempt to determine its location, so that the best procedures can be planned for removal or curing of the problem.

In following such a procedure, in order to place dye in the desired location, a catheter is pushed into the vascular system and by rotating the tube, it is possible to guide the movement of the tip of the catheter through the vascular system from outside the body, the catheter can be pushed through an artery in the arm for example all the way into the heart. Rotation of the catheter during insertion is essential to effect the proper sliding of the catheter through the blood vessel as well as to enable the surgeon to steer the tip of the catheter to its ultimate destination.

In order to preserve the sterile condition of the catheter in so far as possible, the tip end of the catheter and the rotatable delivery tubing for the fluid to be forced through the system are connected to the fluid supply means in a manner so that there need be no break in the delivery line through which bacteria or the like could enter the fluid stream. The catheter is usually connected to the supply line through a swiveling coupling as shown in the patents mentioned above so that the tubing and its tip may be rotated without producing a twisting action throughout the entire liquid supply tube that is connected between the catheter and the source of the fluid.Such a swiveling arrangement has been found most serviceable to enable a catheter to be easily rotated in either direction to any desired degree so that it may be more easily manipulated to guide it through the vascular system as described above.

The structure described herein is an improved form of a swiveling connector for use between a catheter that must be rotated to aid its insertion into a blood vessel or the like and the relatively stationary fluid supply means to which the catheter is connected as is required in the procedures described above. The improvement provides a greatly simplified structure as compared with the known swiveling connectors.

The essential ability to rotate the tip end and tubing of the catheter relative to the fluid supply line is retained and a device is here shown that has a minimum number of parts and one that can be quite easily manufactured of plastic parts to be assembled for use.

Brief Description of the Drawing A sectional view through the assembled swivel connector is shown.

Example of the Preferred Embodiment The swiveling connector here shown is made simply with two concentrically arranged tubular means and includes a tubular female element 10 configured to be assembled with the tubular male element 12. The body of the tubular female element is shaped at one end to form a Luer taper 14 over which the end of the flexible tube 1 6 of the catheter is engaged and held. The female element has a fluid flow passage 20 that has an entrance end 22 and a continuous portion 24 that has a smaller diameter than the entrance end so that a shoulder 26 is formed in the passage. The passage 20 guides fluid into the catheter tubing 16.The outer periphery of the female body may be serrated or formed with ridges 28 so that the female element may be more easily engaged and twisted to rotate the tubing 16 that carries the tip end (not shown) of the catheter while the catheter is being inserted into a blood vessel. The Luer taper 14 may be surrounded by an extension 18 of the female element 10; the inner surface of 18 may be threaded.

The tubular male body 12 is smaller in diameter and includes a nose portion 38 having a circular cross-section to freely rotatably fit into and yet substantially fill the continuing portion 24 of the passage through the female element 10. The male element has a fluid flow passage 34 that delivers fluid from an inlet end 36 into fluid passage 20 of the female element. The inlet 36 is designed to be connected with a conventional connection, such as for example 14 and 1 6 in the Sarns reference or 50 in the Waldbillig reference, to a relatively stationary tube leading from a fluid supply. The male member is provided with a peripheral groove 40 that defines the nose portion 38 and the nose fits into passage 24 so that groove 40 is positioned adjacent shoulder 26.An O-ring seal 42 is fitted into groove 40 and projects over shoulder 26 to provide a rotatable liquid seal between the female and male members.

The male member is axially aligned with flow passage 20 through the female member at its nose end by reason of the rotatable fit of the male member in the continuing portion 24 of that flow passage. The male member has a further bearing engagement with a collar 44 that has a cylindrical end 46 defined by an outer periphery to just fit within the entrance end 22 of the passage through the female element and an inner periphery 48 providing a bearing wall in alignment with the continuing portion 24 of passage 20. The male member 12 is rotatably supported within the inner periphery 48 of collar 44 in alignment with flow passage 20. A fluid conduit (not shown), connects the male member 12 with a supply of fluid to be delivered into the blood vessel.

The collar 44 is preferably cemented in the entrance portion of passage 20 to be permanently assembled with the connector. The collar alternately could be made to be press fitted more or less permanently in place or the entrance portion 22 and collar could be threadedly engaged to make the parts separable. In the preferred throw-away type of device however, the cemented connection is used for ease of manufacture and use.

The device described above is easily sterilized after manufacture and can be delivered to the medical unit in a suitable package ready for use.

After the supply tube has been connected to the coupling portion of the male member and a catheter has been attached to the female element, the swivel connector is ready for use. The catheter may be inserted into the blood vessel and is freely rotatable as it is pushed into place so that the tip of the catheter may be turned as the feeding of the catheter into the blood vessel continues in order to guide the tube into the desired position.

The simple concentrically arranged tubular male and female elements and O-ring assembly together with the plastic collar are inexpensive to make and simple to maintain. This swivel connector can be easily prepared for use and can be discarded after use. If necessary or desirable for some reason, this connector can be made so that the parts can be dismantled and prepared for reuse, but when simply made of two concentrically disposed tubular elements, assembled together as above described, the expense of the labor involved in preparing the connector for reuse would far outweigh the cost of the item so it is usually supplied in the form of a throw-away device.

The swivel coupling or adaptor of the invention can be fabricated of metal or plastic. A major cost advantage is attained when a plastic is used as the base material and the collar 44 is simply cemented in place as described above. Almost any organic polymer, i.e. synthetic resin, can be used but thermoplastics are preferred for their relative ease of formation by e.g. injection molding; acrylonitrile-butadiene-styrene, polycarbonate, and polymethymethacrylate are most desirable.

The collar 44 can be cemented in place by using an actual adhesive which is compatible with the polymer system making up the parts of the coupling, or by solvent cementing with the appropriate solvent. Methyethyl ketone very effectively solvent bonds acrylonitrile-butadienestyrene, while methylene chloride is suitable for polycarbonate and polymethylmethacrylate.

Claims (5)

1. A swiveling connector for a rotatable catheter including relatively movable elements comprising a tubular female element having a stepped flow passage therethrough to form a shoulder therein that divides said passage into an entrance end and a continuing portion, said shoulder being exposed through said entrance end of said passage; a tubular male member having a flow passage therethrough, said male member extending concentrically within said female element through said entrance end and into and filling a part of said continuing portion of said first named passage; said male member having a groove around its periphery in a position to be located adjacent said shoulder, an O-ring seal positioned in said groove and extending beyond said male member and over said shoulder; a collar adapted to surround said male member and be fixedly seated in said entrance end of said passage in the female member, said male member being rotatable within said collar and within said continuing portion of said passage through the female element, and said collar being proportioned to trap said O-ring in said groove and against said shoulder, whereby to provide a swiveling connector having a liquid seal therein.

2. A connector as in claim 1 wherein said continuing portion of said flow passage through the female element has a smaller diameter than the diameter of said entrance end, said male member having a diameter to rotatably fit within said continuing portion, and said collar having an outer diameter to fill said entrance end and an inner diameter to surround and provide a bearing support for said male member.

3. A connector as in claim 2 wherein said male, female, and collar members are all made of synthetic resin materials and said collar is permanently cemented in place in said entrance end of the female member.

4. A connector as in claim 2 wherein said continuing end of said passage through the female member includes a threaded extension, and said collar has a threaded engagement in said entrance end of said female member.

5. A connector as in claim 2 wherein the outer diameter of said collar is designed to have a press fit within the entrance end of said passage through the female element.