GB2356032A

GB2356032A - Cross acting tap

Info

Publication number: GB2356032A
Application number: GB9925801A
Authority: GB
Inventors: Kuldip Gill
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-11-02
Filing date: 1999-11-02
Publication date: 2001-05-09
Also published as: GB9925801D0

Abstract

A cross acting tap T which includes a flow member 1, a cross member 2 and a valve member 6. The flow member 1 has an inlet 3 and an outlet 4. The cross member 2 has a passage which intersects the flow member 1, this passage acts as a guide to the valve member 6. The valve member 6 has a through opening 7 and is longitudinally moveable in the cross member passage. In a first position, the valve member 6 prevents flow of fluid along the passage of the flow member whilst in a second position opening 7 is aligned with the flow passage and flow allowed. The valve member 6 is constrained against rotation within the cross member 2 and the through opening 7 has a greater cross sectional area at one end 8 than the opposite end 9. The cross member and valve member may be of part circular and part flat cross section with the smaller opening 9 being within the flat portion. A localised restriction 10 in the flow passage may be included.

Description

2356032 Title: Cross Acting Tap Descdption of Invention This invention

relates to a cross acting tap and more particularly, but not exclusively, to a cross acting tap for releasing fluid from a bag such as a urine drainage bag.

A bag holding a fluid, such as a urine drainage bag, may have a tap which may be opened to empty the fluid out of the bag. The tap must be easy to open and must not permit any leakage of fluid out of the bag.

One known tap has a flow member which has an inlet part and an outlet part, and a cross-member which is arranged generally perpendicular to the flow member. The cross-member contains a valve member which is movable within the cross-member from a first position, in which the valve member closes the flow member and prevents the flow of fluid through the flow member, to a second position in which the fluid may flow through the flow member. The inlet part in use is attached to a bag or other container via a fitting means and the outlet part may be connected to a tube so when the valve member is in the second, open, position the fluid may flow from the bag though the flow member and the tube. Both the tube and the fitting means are generally of a standardised size, and the external diameters of the inlet and outlet parts need therefore to be of a correct size to enable fluid-tight seals to be achieved between the tap and the bag, and the tap and the tube.

In this known cross-acting tap, the flow member and the cross-member both have a circular cross-section, and the valve member which is received in the cross-member also has a circular cross-section and is dimensioned to fit closely in the cross-member thus to form a fluid tight seal. The valve member has a first and second part connected by a connecting member, both of the first and second parts having a circular cross-section. The connecting member has 2 a diameter substantially less than the internal diameter of the cross- member and a length generally similar to, or greater than, the internal diameter of the flow member. When the valve member is in the second position, the connecting member is positioned across the flow member and the fluid flows through the flow member around the connecting member. A disadvantage of this configuration of tap is that the presence of the connecting member restricts the flow of fluid, thus increasing the time taken to empty the bag, and also can turbulate the flow.

In an alternative known configuration of cross-acting tap the valve member has only a first part which is dimensioned to fit closely in the crossmember and which incRides a through opening through which fluid may flow when the valve member is in the second position. The diameter of the through opening is generally the same as the internal diameter of the flow member, and as there is nothing crossing the flow member, fluid flow is not restricted. If the cross-member and valve member have a circular cross-section, however, the valve member may be rotated when inside the cross-member and this can give rise to mis-alignment of the through opening and the flow member so that the flow member may be partially or completely blocked when the valve member is in the second position.

To solve this problem it is known to provide an otherwise circular crosssection cross-member and corresponding valve member, each with corresponding flat surfaces. The flat surfaces are normal to the flow member, and prevent the valve member from rotating inside the crossmember. A through opening is provided through the valve member and has a first end which opens to the circular cross section part opposite to the flat surface, and extends through the valve member to a second end at the flat surface. The through opening has a generally constant circular cross section along its length.

3 In order to achieve an optimum seal, the diameter of the through opening must be less than the width of the flat surface. Thus the maximum diameter of the through opening is determined by the width of the flat surface.

To achieve maximum rate of liquid flow through the tap, it is desirable that the diameter of the through opening and hence also the width of the flat surface are as large as possible. In order to reduce the probability of the tap leaking, however, it is desirable that the flat surface is as narrow as possible, since the probability of leakage decreases as the area of the circular section increases. Thus the width of the flat surface is chosen as a compromise between these two conflicting factors.

According to one aspect of the invention we provide a cross acting tap including a flow member, a cross member and a valve member, the flow member having an inlet part and an outlet part, and a passage therethrough for the flow of fluid, the cross member having a passage which crosses the passage of the flow member, the valve member being accommodated in the passage of the cross member and having a through opening, the valve member being longitudinally moveable in the passage of the cross member from a first position in which the valve member prevents the flow of fluid along the passage of the flow member and a second position in which the through opening of the valve member is aligned with the passage of the flow member so that fluid may flow along the passage of the flow member from the inlet part to the outlet part, characterised in that the valve member is constrained against rotation in the passage of the cross member and the through opening of the valve member has a greater cross-sectional area at one end than at an opposite end.

The passage of the cross member and the valve member may be of corresponding part circular cross section and may have corresponding flat surfaces, thus to constrain the valve member against rotation in the passage The smaller cross-sectional area end of the through opening of the valve 4 member may open at the flat surface. The width of the flat surface may be less than half the diameter of the otherwise circular valve member.

The flow passage of the flow member may be of substantially constant cross sectional area throughout its length, but having a localised restriction adjacent the flat of the cross member where the flow passage and the passage of the cross member intersect, to reduce the cross sectional area of the flow passage towards the cross sectional area of the smaller cross sectional area end of the through opening of the valve member.

Thus the rate of fluid flow through the tap can be maximised without increasing the leakage probability, as the provision of a local restriction in fluid flow will not seriously adversely affect fluid flow.

In a preferred arrangement, the flow passage of the flow member may be substantially circular throughout its length and the localised restriction may be an inwardly extending circumferential lip.

The external cross sectional areas of the flow member and the cross member may be substantially the same.

The smaller cross sectional area end of the through opening of the valve member may be, when the valve member is in the second position, adjacent the outlet part of the flow the flow member.

The through opening of the valve member may be circular in cross section and the diameter of the opening may change smoothly from the end of greater cross sectional area to the end of smaller cross sectional area.

The flow member and valve member may be arranged with their longitudinal axes at approximately 90' to each other.

The invention will now be described with reference to the accompanying drawings in which:

Figure I is a cross section through the tap when closed; Figure 2 is a side view of the tap.

Referring now to the figures, there is shown a tap T including a flow member 1 and a cross member 2 which is arranged perpendicular to the flow member 1. The flow member I includes an inlet part 3 and an outlet part 4 and a passage therethrough for the flow of fluid. Both the inlet and outlet parts 3, 4 are tubes each with a generally circular cross section and nominally the same internal and external diameters. The cross member 2 has a passage which crosses the passage of the flow member I and is also a tube, but has a part circular cross section and a flat surface 5 along the length of the tube. The flat surface 5 lies along an interface between the outlet part 4 and the cross member 2 and is generally perpendicular to a longitudinal axis of the flow member 1.

A valve member 6 is accommodated in the passage of the cross member 2. The valve member 6 also has a part circular cross section with a flat surface along its length and has dimensions close to the internal dimensions of the cross member 2 so it forms a tight seal with the cross member 2. There is a through opening 7 with a circular cross-section extending through the valve member 6 with its longitudinal axis parallel to the longitudinal axis of the flow member 1.

The valve member 6 is movable longitudinally in the passage of the cross member 2 between a first position, shown in Figure 1, in which the valve member 6 closes the flow member I and prevents the flow of fluid through the passage of the flow member 1, and a second position in which the through opening 7 is positioned in the flow member I and allows the flow of fluid through the passage of the flow member 1.

The through opening has a first end 8 which opens at the part circular cross section side of the valve member 6, and a second end 9 which opens at an opposite position, in the flat surface of the valve member 6. The first end 8 has a greater diameter than the second end 9, and the diameter of the through opening 7 decreases gradually from the first end 8 to the second end 9.

The flow passage of the flow member I is of substantially constant cross sectional area throughout its length, but has a localised restriction adjacent to 6 the flat of the cross member 2 where the flow passage and the passage of the cross member 2 intersect. The localised restriction is a lip 10 extending inwardly around the circumference of the outlet part 4 of the flow member which reduces the cross sectional area of the flow passage towards the cross sectional area of the smaller cross sectional area end of the valve member.

There are three circumferential ridges around the outside of the inlet part 3, which,, when the inlet part 3 is inserted into an appropriately dimensioned tube, holds the tube in place on the inlet part 3. Such a tube may form a fitting means for attaching the tap T to a bag or other such container. Such ridges may also be present on the outlet part 4 of the flow member I to facilitate the attachment of a tube to the outlet part 4.

The flow member 1, cross member 2 and valve member 6 may be fabricated from plastic by extrusion moulding.

While the flow member I and cross member 2 preferably have circular and part circular cross sections respectively, their cross sections may be a different shape, square for example.

The flow member I and cross member 2 preferably have generally the same cross sectional areas, but may have substantially different cross sectional areas. Similarly, although the inlet 3 and outlet 4 parts preferably have generally the same cross sectional areas, they may also have different cross sectional areas to each other and the cross section of each need not be generally constant.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof

Claims

7 CLAIMS

1. A cross acting tap including a flow member, a cross member, and a valve member, the flow member having an inlet part, an outlet part, and a passage therethrough for the flow of fluid, the cross member having a passage which crosses the passage of the flow member, the valve member being accommodated in the passage of the cross member and having a through opening, the valve member being Iongitudinally moveable in the passage of the cross member from a first position in which the valve member prevents the flow of fluid along the passage of the flow member and a second position in which the through opening of the valve member is aligned with the passage of the flow member so that fluid may flow along the passage of the flow member from the inlet part to the outlet part, characterised in that the valve member is constrained against rotation in the passage of the cross member and the through opening of the valve member has a greater cross sectional area at one end than at an opposite end.

2. A tap according to claim I characterised in that the passage of the cross member and the valve member are of corresponding part circular configuration thus to constrain the valve member against rotation in the passage.

Z:-

3. A tap according to claim 2 cbaracterised in that the passage of the cross member and the valve member have corresponding flat surfaces, the smaller cross sectional area end of the through opening of the valve member opening at the flat surface.

4. A tap according to claim 3 characterised in that the width of the flat is less that half the diameter of the otherwise circular valve member.

8

5. A tap according to claim 3 or claim 4 characterised in that the flow passage of the flow member is of substantially constant cross sectional area throughout its length, but having a locallsed restriction adjacent the flat of the cross member where the flow passage and the passage of the cross member intersect, to reduce the cross sectional area of the flow passage towards the cross sectional area of the smaller cross sectional area end of the through opening of the valve member.

6. A tap according to any one of the preceding claims characterised in that the flow passage of the flow member is substantially circular throughout its length.

7. A tap according to claim 6 where appendant to claim 5 characterised in the localised restriction is an inwardly extending circumferential lip.

8. A tap according to any one of the preceding claims characterised in that the cross sectional areas of the flow member and the cross member are substantially the same.

9. A tap according to any one of the preceding claims characterised in that the smaller cross sectional area end of the through opening of the valve member 0 is, when the valve member is in the second position, adjacent the outlet part of the flow member.

10. A tap according to any one of the preceding claims characterised in that the through opening of the valve member is circular in cross section and the diameter of the opening changes smoothly from the end of greater cross sectional area to the end of smaller cross sectional area.

9

11. A tap according to any preceding claim wherein the flow member and valve member are arranged with their longitudinal axes at approximately 90" to each other.

12. A cross acting tap substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

13. Any novel feature or novel combination of features described herein and/or shown in the accompanying drawings.