Flexible double lumen tube and a tube coupling system for same

1. A tube coupling system comprising a first tube coupling component comprising

a male coupling part opposite a respective female coupling part, and

a second tube coupling component comprising

a first end fitting opposite a respective second end fitting,

wherein the first tube coupling component has a first interior pipe that extends axially inside a first exterior pipe, the first interior pipe and the first exterior pipe being concentric,

wherein the second tube coupling component has a second interior pipe that extends axially inside a second exterior pipe, the second interior pipe and the second exterior pipe being concentric,

wherein the female coupling part of the first tube coupling component has a first exterior pipe section which has a seat for a gasket, which seat has its bottom at a transmission between the male coupling part and the female coupling part, which the gasket has a gasket bottom with a central opening for passage of the second interior pipe of the first end fitting, the gasket bottom extends into a circumferential gasket wall provided with a plurality of annularly, spaced apart, flow openings for establishing fluid communication between a gap between the second interior pipe and the second exterior pipe of the second tube coupling component, and between a gap between the first interior pipe and the first exterior pipe of the male coupling part of the first tube coupling component, and

wherein a free gasket end of the gasket opposite the gasket bottom constitutes a sealing ring between the second exterior pipe and the first exterior pipe above the plurality of flow openings.

2. The tube coupling system according to claim 1 , wherein the second interior pipe protrudes axially beyond the second exterior pipe with a pipe extension at the first end fitting of the second tube coupling component, but not at the second end fitting of said second tube coupling component.

3. The tube coupling system according to claim 1 , wherein the first interior pipe and the second exterior pipe are kept in annular spaced apart relationship by means of spacers that extends radially between said second interior pipe and said second exterior pipe, optionally the spacers are ribs or struts.

4. The tube coupling system according to claim 1 , wherein the second end fitting of the second tube coupling component and the male coupling part of the first tube coupling component have the same cross-section.

5. The tube coupling system according to claim 1 , wherein the overall shape of the first tube coupling component has a funnel-shape, wherein the female coupling part is wider than the male coupling part, and in that the first exterior pipe has various diameters along its length.

6. The tube coupling system according to claim 1 , wherein the female coupling part of the first tube coupling component has a first circumferential wall in axial extension of the first exterior pipe of the male coupling part, wherein the first circumferential wall delimits the first exterior pipe section of increased exterior diameter in relation to the exterior diameter of the male coupling part, the first circumferential wall extends axially into a second exterior pipe section of increased exterior diameter in relation to the exterior diameter of the first exterior pipe section.

7. The tube coupling system according to claim 1 , wherein a circumferential wall of the first tube coupling component of the female coupling part has opposite first and second lock slots for slidingly, crosswise the longitudinal axis of the first tube coupling component, receiving a first ring-shaped lock component adapted to, at least temporarily, lock the first end fitting of the second coupling component together with the first tube coupling component.

8. The tube coupling system according to claim 7 , wherein the first ring-shaped lock component has a first end that, via opposite exterior straight slide surfaces, extends into an opposite second end, optionally said first end curves away from said opposite second end, optionally following the exterior curvature of the female coupling part, and wherein a hole of the first ring-shaped lock component serves for inserting the first end fitting.

9. The tube coupling system according to claim 1 , wherein the first tube coupling component is a single piece.

10. An irrigation system comprising the tube coupling system according to claim 8 , a double lumen irrigation device, and an annular double lumen tube, wherein the tube coupling system inter-couples the double lumen irrigation device and the annular double lumen tube.