Infusion unit for producing coffee suitable for washing in the dishwasher

1. A dishwasher washable removable infusion unit for producing hot beverages, the infusion unit comprising:

an infusion chamber comprising a fixed portion and a moving portion;

a mechanism coupled to the infusion chamber for opening and closing said infusion chamber;

a supporting structure having at least two sides enclosing the infusion chamber and the mechanism, each side comprising a plurality of openings and respective structure guides including a plurality of second openings, the openings and second openings providing access to said infusion chamber and said mechanism; and

a plurality of kinematic pairs having elements formed with different self-lubricating properties.

2. The infusion unit as claimed in claim 1 , wherein in each pair one of said elements is made of a plastic self-lubricating material selected from at least one of molybdenum, graphite, and polytetrafluoroethylene and the other of said elements is made of a plastic not comprising the material.

3. The infusion unit as claimed in claim 1 , further comprising a motor shaft to operate the mechanism, and having shaft supports for self supporting in said supporting structure, wherein said shaft supports and said motor shaft form a kinematic pair.

4. The infusion unit as claimed in claim 3 , wherein the moving portion includes chamber guides, and further comprising a pivoting arm attached to said motor shaft and having arm sliders for sliding in the chamber guides, said arm sliders and said chamber guides form a kinematic pair.

5. The infusion unit as claimed in claim 1 , wherein said moving portion includes second sliders engaging the structure guides and extend in an opening and closing direction of the infusion chamber, said structure guides and the corresponding second sliders form a respective kinematic pair.

6. The infusion unit as claimed in claim 1 , further comprising a control lever connected to a base of the infusion chamber for controlling a movement of the base with respect to the moving portion, said second supports and said control lever forming a kinematic pair.

7. The infusion unit as claimed in claim 1 , wherein said supporting structure comprises sides between which said infusion chamber and the mechanism are supported.

8. The infusion unit as claimed in claim 7 , wherein at least one of said sides is provided with said openings.

9. The infusion unit as claimed in claim 1 , wherein said openings are formed by a plurality of linear elements that provide a mechanical load-bearing structure for the infusion chamber and mechanism.

10. The infusion unit as claimed in claim 9 , wherein said openings define a framework structure.

11. The infusion unit as claimed in claim 10 , wherein said linear elements extend according to trends defined by force lines in said sides.

12. The infusion unit as claimed in claim 10 , wherein said linear elements are curved.

13. The infusion unit as claimed in claim 10 , further comprising a supporting seat connected to a motor shaft by the linear elements to perimeter edges of said supporting structure.

14. The infusion unit as claimed in claim 13 , wherein the moving portion includes chamber guides that extend from said supporting seat and include through openings for washing.

15. The infusion unit as claimed in claim 14 , wherein said chamber guides are joined at edges of said supporting structure by the linear elements.

16. The infusion unit as claimed in claim 14 , wherein said chamber guides terminate at the supporting seat for constraining the fixed portion.

17. The infusion unit as claimed in claim 9 , wherein said linear elements have an elongated cross section with a smaller transverse dimension and a larger transverse dimension extending orthogonal to the supporting structure.

18. The infusion unit as claimed in claim 1 , wherein said supporting structure is made of self-lubricating material.

19. The infusion unit as claimed in claim 18 , wherein said supporting structure is made of a plastic material to which a lubricating material is added.

20. The infusion unit as claimed in claim 7 , wherein said sides are joined by a plurality of crossbars and each side includes linear elements defining a framework structure configured to transfer stresses exerted on the framework structure by forces acting on the fixed and moving portions towards said crossbars.

21. The infusion unit as claimed in claim 20 , wherein each of said sides comprises an area surrounding a support for a motor shaft for opening and closing the infusion chamber and a plurality of linear elements that transfer stresses exerted on the shaft support towards the base of the respective side.

22. The infusion unit as claimed in claim 21 , wherein said linear elements comprise at least one arch element having a curve and configured to join crossbars positioned along the base of the respective side, and to the extrados of which at least part of forces applied to the shaft support are transferred.

23. The infusion unit as claimed m claim 22 , wherein each side comprises a base and a bottom linear element joins said crossbars positioned along the base of the side.

24. The infusion unit as claimed in claim 23 , wherein a linear edge element extends from the base of each side for joining one of the crossbars of the base to an upper crossbar thereby connecting the two sides, the linear edge element is positioned higher than the support of the motor shaft.

25. The infusion unit as claimed in claim 24 , wherein the arch element is provided on each side to connect the base of the side to said linear edge element, in an intermediate position between the crossbar of the base and the upper crossbar.

26. The infusion unit as claimed in claim 24 , wherein each side comprises a connection that joins the area surrounding the shaft support to said upper crossbar.

27. The infusion unit as claimed in claim 26 , wherein said connection comprises at least one joint linear element.

28. The infusion unit as claimed in claim 27 , wherein said joint linear element is arched.

29. The infusion unit as claimed in claim 27 , wherein said connection comprises two joint linear elements.

30. The infusion unit as claimed in claim 7 , wherein said supporting structure comprises, in proximity to said fixed portion, a plurality of crossbars joining the sides adjacent to the fixed portion.

31. The infusion unit as claimed in claim 30 , wherein said crossbars adjacent to the fixed portion are joined to each other by an arched connection on each of said sides.

32. The infusion unit as claimed in claim 31 , wherein said arched connection has an extrados facing an axis of a motor shaft for opening and closing the infusion chamber.

33. The infusion unit as claimed in claim 31 , wherein said arch connection has a double arch structure.

34. The infusion unit as claimed in claim 33 , wherein said double arch structure comprises fins reciprocally connecting two substantially parallel arch connections.

35. The infusion unit as claimed in claim 32 , wherein on each side said arched connection is joined, by a substantially rectilinear element to an area supporting the motor shaft.

36. The infusion unit as claimed in claim 35 , wherein said substantially rectilinear element extends from the top of the arched connection towards the axis of the motor shaft.

37. The infusion unit as claimed in claim 34 , wherein said substantially rectilinear element forms a guide for the closing movement of the infusion chamber.

38. The infusion unit as claimed in claim 34 , wherein said substantially rectilinear element is joined, by means of an arch structure to linear elements defining the edge of the respective side, extending approximately parallel to said substantially rectilinear element.

39. The infusion unit as claimed in claim 38 , wherein said arch structure has an extrados facing the crossbars adjacent to the fixed portion.

40. The infusion unit as claimed in claim 39 , wherein said substantially rectilinear element is connected to said linear elements forming edges of the sides, by a plurality of auxiliary linear elements, distributed along the longitudinal extension of the substantially rectilinear element.

41. The infusion unit as claimed in claim 40 , wherein said auxiliary linear elements have an arched shaped.

42. The infusion unit as claimed in claim 41 , wherein said auxiliary linear elements have a concavity facing the axis of the motor shaft.

43. The infusion unit as claimed in claim 1 , wherein said supporting structure is made of polyoxymethylene.

44. The infusion unit as claimed in claim 1 , wherein one of the kinematic elements in the kinematic pairs is made of material selected from at least one of molybdenum, graphite, and polytetrafluoroethylene.

45. The infusion unit as claimed in claim 1 , further comprising a lip seal positioned between said fixed portion and moving portion.

46. The infusion unit as claimed in claim 2 , further comprising a motor shaft to operate the opening and closing mechanism of the infusion chamber, supported in supports produced in said supporting structure, and wherein said shaft supports and said motor shaft form a kinematic pair.

47. The infusion unit as claimed in claim 2 , wherein the supporting structure includes structure guides and said moving portion includes second sliders engaging the structure guides and extending in an opening and closing direction of the infusion chamber, and each of said structure guides and the corresponding second slider form a respective kinematic pair.