We Claim:
1. A device (1) for agitating fluid, such as paint, contained inside a receptacle (20), such as a can, said device (1) comprising an agitating shaft (2) that can be driven in rotation, a stirring element (3) and means (4) for linking between the stirring element (3) and the agitating shaft (2), the agitating shaft (2) being positionable from its lower end (5) in the direction of its upper end (6) vertically, in the use configuration, and the stirring element (3) comprising a circular ring portion (7) partially surrounding the agitating shaft (2), this ring portion (7) being, in the vertical position of the agitating shaft (2) corresponding to the use configuration, arranged in a plane that is inclined relative to the agitating shaft (2) and developing about the agitating shaft (2) from one of the "lower" (8) ends thereof in the direction of the other "upper" (9) end thereof, following an ascending slope, this ring portion (7) forming, in the manner of an annular cage, a hollow ring portion provided with openings (11) for communication between its cavity (10) and the exterior, characterized in that the means (4) for linking between the agitating shaft (2) and the stirring element (3) comprise at least one arm (12) that is radial relative to the agitating shaft (2) arranged between the lower end (5) of the agitating shaft (2) and the lower end (8) of the stirring element (3) and connecting said lower ends (5, 8) together, this radial arm (12), which is capable of acting as a scraper and called the lower linking arm (12), extending at least partially in a plane perpendicular to the agitating shaft (2).
2. The device (1) as claimed in claim 1,
characterized in that the lower linking arm (12) takes the form of a blade (120) having, taken relative to the direction of rotation of the agitating shaft (2), a front longitudinal or leading edge (121), a rear longitudinal edge (122), in that said front (121) and rear (122) longitudinal edges are connected together via two faces forming, respectively, the faces of the top (123) and of the bottom (124) of the blade (120), in the use configuration of the agitating shaft (2), in that the front longitudinal edge (121) of the blade (120) extends in a plane perpendicular to the agitating shaft (2), and in that the face of the top (123) of the blade (120)

forms an inclined surface with a descending slope from the rear longitudinal edge (122) toward the front longitudinal edge (121).
3. The device (1) as claimed in claim 2,
characterized in that the face of the top (123) of the blade (120) constituting the lower linking arm (12) is concave.
4. The device (1) as claimed in one of claims 1 to 3,
characterized in that the means (4) for linking between the agitating shaft (2) and the stirring element (3) comprise, in addition to the lower linking arm (12), at least one supplementary arm (13, 14) that is radial relative to the agitating shaft (2).
5. The device (1) as claimed in claim 4,
characterized in that the or at least one of the supplementary shafts (13, 14) take the form of a blade (130, 140) having, taken relative to the direction of rotation of the agitating shaft (2), a front longitudinal or leading edge (131, 141), a rear longitudinal edge (132, 142), in that said front (131, 141) and rear (132, 142) longitudinal edges are connected together via two faces form ing, respectively, the faces of the top (133, 143) and of the bottom (134, 144) of the blade (130, 140), in the use configuration of the agitating shaft (2), and in that the face of the top (133, 143) of the blade (130, 140) forms an inclined surface with a descending slope from the rear longitudinal edge (132, 142) toward the front longitudinal edge (131, 141).
6. The device (1) as claimed in either of claims 4 and 5,
characterized in that the or each of the supplementary arms (13, 14) is offset axially along the agitating shaft (2) relative to the lower linking arm (12).
7. The device (1) as claimed in one of claims 4 to 6,
characterized in that the or one of the supplementary arms (13, 14) is arranged between the agitating shaft (2) and the upper end (9) of the ring portion (7) of

the stilling element.
8. The device (1) as claimed in one of claims 1 to 7,
characterized in that the lower end (8) of the ring portion (7) has, in the zone of connection thereof to the lower linking arm (12), a trough portion (15) forming a ramp.
9. The device (1) as claimed in one of claims 1 to 8,
characterized in that the ring portion (7) is formed from two concentric parallel circle portions (16), partially surrounding the agitating shaft (2), these two circle portions (16), of different radii, being connected together by half-rings (17) each extending in a plane that is radial relative to the agitating shaft (2).
10. The device (1) as claimed in claim 9,
characterized in that the half-rings (17) are organized in two series (171, 172), extending, respectively, one (171) above the plane passing via the two circle portions (16), the other (172) below the plane passing via the two circle portions (16), in the use configuration of the agitating shaft (2).
11. The device (1) as claimed in either of claims 9 and 10,
characterized in that the half-rings (17) are offset axially along the circle portions (16) from one series of half-rings to the other series of half-rings.
12. The device (1) as claimed in one of claims 1 to 11,
characterized in that the stirring element (3), the means (4) for linking between the stirring element (3) and the agitating shaft (2) and at least a part of the agitating shaft (2) are made as a single piece.
13. The device (1) as claimed in one of claims 1 to 12,
characterized in that the ring portion (7) develops between the lower end (8) thereof and the upper end (9) thereof over at least 90°, preferably 180°.

14. The device (1) as claimed in one of claims 1 to 13,
characterized in that the angular sector formed by the ring portion (7) is within the range 90° - 270°.
15. A lid (21) of a receptacle (20) for receiving fluid, said lid (21) being provided
with a device (1) for agitating fluid,
characterized in that the device (1) for agitating fluid is as claimed in one of claims 1 to 14.