NZ549380A - Infusion and/or withdrawal fitting for biomedical fluid circuits - Google Patents

Abstract

An infusion and/or withdrawal fitting for biomedical fluid circuits is defined by a tubular conduit (2) having a first end (7) connectable to a biomedical fluid circuit, and a second end (6) which is closed by a plug (9) having a collar (14) connected to the plug (9) at a weakened portion (18); the conduit (2) having a breaking member (21) for breaking the weakened portion (18) when fitting the plug (9) to the conduit (2), and for retaining the collar (14) on the conduit (2).

Description

INFUSION AND/OR WITHDRAWAL FITTING FOR BIOMEDICAL FLUID CIRCUITS TECHNICAL FIELD The present invention relates to an infusion and/or withdrawal fitting for biomedical fluid circuits.

More specifically, the present invention relates to an infusion and/or withdrawal fitting for biomedical 15 fluid circuits, of the type comprising a tubular conduit having a first end connectable to a biomedical fluid circuit, and a second end closed by a cap.

BACKGROUND ART The cap normally comprises a plug movable between an 20 open position and a closed position opening and closing the second end respectively; and an elastically deformable collar fitted to the conduit and connected to the plug by a flexible element to keep the plug and collar connected to each other when the plug is in the 25 open position.

Known infusion and/or withdrawal fittings of the type described above have several drawbacks, mainly due to assembly of the collar to the conduit being relatively 2 complicated, by requiring elastic deformation of the collar by the user.

A further drawback of known infusion and/or withdrawal fittings of the type described above lies in 5 the relative ease with which the collar works loose from the conduit.

DISCLOSURE OF INVENTION It is an object of the present invention to provide an infusion and/or withdrawal fitting for biomedical 10 fluid circuits, designed to eliminate the aforementioned drawbacks.

According to the present invention, there is provided an infusion and/or withdrawal fitting for biomedical fluid circuits, as claimed in Claim 1. 15 BRIEF DESCRIPTION OF THE DRAWINGS A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which: Figures 1 to 3 show longitudinal sections, with 20 parts enlarged for clarity, of a preferred embodiment of the infusion and/or withdrawal fitting according to the present invention in different operating positions.

BEST MODE FOR CARRYING OUT THE INVENTION Number 1 in Figure 1 indicates as a whole an 25 infusion and/or withdrawal fitting for biomedical fluid circuits (not shown).

Fitting 1 comprises a tubular conduit 2, which has a given longitudinal axis 3, is defined axially by two 3 surfaces 4 substantially perpendicular to axis 3, is defined internally by a substantially truncated-cone-shaped surface 5, and in turn comprises a wide, substantially cylindrical top portion 6, and a narrow, 5 substantially truncated-cone-shaped bottom portion 7 connectable to a biomedical fluid circuit (not shown).

Portion 6 is closed by a cap 8 comprising a plug 9, which has a given longitudinal axis 10, is substantially cup-shaped, is defined internally by an annular end wall 10 11 substantially perpendicular to axis 10, and by a substantially cylindrical lateral wall 12, and is closed axially, at wall 11, by a central shank 13, which projects axially from wall 11, is substantially in the form of a truncated-cone-shaped cup with the same taper 15 as surface 5, and has a concavity opposite the concavity of plug 9.

Plug 9 also has an annular collar 14, which is substantially coaxial with axis 10, is defined internally by a lateral wall 15 comprising a cylindrical portion 16 20 coplanar with wall 12, and a truncated-cone-shaped portion 17, and is joined to plug 9 at a pre-cut weakened portion 18 defined by a number of teeth 19 substantially parallel to and equally spaced about axis 10.

Portion 6 and plug 9 are connectable by means of a 25 threaded coupling 20, and with shank 13 engaging portion 6 (Figure 2) .

As shown in Figure 2, when screwing cap 8 to portion 6, teeth 19 of weakened portion 18 are broken by a 4 breaking device 21 comprising an annular flange 22 extending outwards from the outer surface of portion 6.

Flange 22 tapers outwards and is defined by two facing, substantially truncated-cone-shaped surfaces 23 5 and 24, which are connected to each other by a substantially cylindrical surface 2 5 coaxial with axis 3 and connected to surface 23, and by an annular surface 26 located between surfaces 24 and 25 and perpendicular to surface 25.

With reference to Figures 2 and 3, once teeth 19 are broken, flange 22 is located between plug 9 and collar 14 to retain collar 14 on conduit 2, collar 14 is connected in rotary manner to conduit 2, and plug 9 is movable between an open position and a closed position opening 15 and closing portion 6 respectively.

In the open position opening portion 6, plug 9 is kept joined to collar 14 by a flexible element 27 extending between plug 9 and collar 14 and formed in one piece with plug 9 and collar 14.

WO 2005/079907 PCT/IT2004/000079

Claims (11)

1) An infusion and/or withdrawal fitting for biomedical fluid circuits, the fitting comprising a 5 tubular conduit (2) having a first end (7) connectable to a biomedical fluid circuit, and a second end (6) ; and a cap (8) which fits onto said second end (5), the cap (8) comprising a plug (9) movable between an open position and a closed position opening and closing the second end 10 (6) respectively, a collar (14), and connecting means (27) for keeping the plug (9) connected to the collar (14) when the plug (9) is in said open position; and the fitting being characterized in that the cap (8) comprises a weakened portion (18) connecting the plug (9) to the 15 collar (14) ; the conduit (2) comprising breaking means (21) for breaking the weakened portion (18) when fitting the cap (8) to said second end (6) , so as to detach the plug (9) from the collar (14) , and for retaining the collar (14) on the conduit (2). 20 2) A fitting as claimed in Claim 1, wherein said breaking means (21) comprise an annular flange (22) projecting outwards from an outer surface of said conduit (

2) .

3) A fitting as claimed in Claim 2, wherein said 25 flange (22) tapers outwards.

4) A fitting as claimed in Claim 2 or 3, wherein said flange (22) is defined by a substantially truncated-cone-shaped first surface (23), by a substantially WO 2005/079907 6 PCT/IT2004/000079 truncated-cone-shaped second surface (24), and by a substantially cylindrical third surface (25) located between said first and said second surface (23, 24).

5) A fitting as claimed in Claim 4, wherein said 5 flange (22) is also defined by an annular fourth surface (26) located between said second and said third surface (24, 25).

6) A fitting as claimed in Claim 5, wherein said third and said fourth surface (25, 26) are substantially 10 perpendicular to each other.

7) A fitting as claimed in any one of the foregoing Claims, wherein the cap (8) has a given longitudinal axis (10) ; said weakened portion (18) being a pre-cut portion comprising a number of teeth (19) distributed about said 15 axis (10) and connecting the collar (14) and the plug (9) •

8) A fitting as claimed in any one of the foregoing Claims, wherein said connecting means (27) comprise a flexible element (27) interposed between said plug (9) 20 and said collar (14) .

9) A fitting as claimed in Claim 8, wherein the flexible element (27) is formed in one piece with said plug (9) and said collar (14).

10) A fitting as claimed in any one of the foregoing 25 Claims, and comprising screw coupling means (20) for connecting said cap (8) and said second end (6). 7

11) A fitting substantially as hereinbefore described with reference to the accompanying drawings.