A threaded plug with a sealing ring

Abstract

 The present invention relates to a threaded plug (1) with a sealing ring (4), said threaded plug comprising a head (2) and a threaded part (3). A flange (5) is provided between the head and the threaded part to cooperate with the sealing ring, which is mounted on the side of the flange which adjoins the threaded part. The flange is provided with a projection (16) which extends continuously on the entire face of the flange which faces toward the sealing ring. In a preferred embodiment, the sealing ring may be provided with one or more thickenings (18).

Description

The prior art

[0001] The present invention relates to a threaded plug with a sealing ring, said threaded plug comprising a head and a threaded part, wherein a flange is provided between the head and the threaded part to cooperate with the sealing ring, which is mounted on the side of the flange which faces toward the threaded part.

[0002] Threaded plugs are widely used for reliable closure of filling and discharge openings in e.g. water and oil tanks, hydraulic cylinders, etc. The threaded plugs are screwed into openings in containers to close the openings. The openings are equipped with threads which correspond to the threads on the threaded plug.

[0003] Generally, there is a wide range of threaded plugs made in various sizes and shapes and in various materials. These may comprise sealing rings, which are e.g. to be heated with a view to adaptation, or loose sealing rings may be involved.

The object of the invention

[0004] The object of the present invention is to provide a threaded plug having improved properties, in particular as regards tightness. The threaded plug according to the invention is also easy to manufacture.

[0005] Thus, the present invention relates to a threaded plug with a sealing ring, said threaded plug comprising a head and a threaded part, wherein a flange is provided between the head and the threaded part to cooperate with the sealing ring, which is mounted on the side of the flange which adjoins the threaded part, and wherein the flange is provided with a projection having a tapered cross-sebtional shape, which extends continuously on the entire face of the flange which faces toward the sealing ring.

[0006] The head on the threaded plug may be configured in various ways according to the specific use, For instance, the head may be configured with a hexagonal cross-sectional area, so that the threaded plug may be tightened or loosened with a fork wrench, or the head may be provided with a notch so that the plug may be tightened or loosened with a screwdriver.

[0007] Preferably, the threaded part is cylindrical and provided with threads on the outer surface, Both the cylindrical part, which constitutes the threaded part, and the head may be hollow or of solid material. The threads are configured so as to correspond to the threads in the openings which the threaded plug is to close.

[0008] The threaded plug and the sealing ring are mating and coherent units, although it will be possible to separate them. I some embodiments, the sealing ring may be secured detachably to the threaded plug. It is also possible to supply the threaded plug and the sealing ring as separate units, which are not assembled till in connection with the use.

[0009] The threaded plug with sealing ring according to the invention contributes to a better seal when containers are closed with the plug. This is owing to the special configuration of the flange with a projection which extends continuously on that one of the two faces of the flange which faces toward the sealing ring. The projection may also be considered a bulge on the flange which can press against a substrate. Hereby, the flange with projection can press harder against a substrate in the form of a sealing ring or gasket when the threaded plug is screwed into an opening which is to be closed, thereby ensuring an effective seal around the opening.

[0010] Typically, the flange has a ring shape or circular shape and has an extent which extends substantially perpendicularly relative to the centre axis of the cylindrical part of the threaded plug. Since the flange is circular or ring-shaped, it is preferred that the projection on the flange extends substantially in a circular shape. The flange may be provided with several projections, of course, which may then be disposed like rings inside one another on the face of the flange.

[0011] In principle, the projection extending on the one face of the flange may have any desired shape or cross-section, The cross-section may have the shape of a semicircle, quadrangle, triangle or the like. In some embodiments, it is preferred that the cross-section has a triangular shape, which means that the projection has a tapered shape, which allows the projection to be pressed effectively against the sealing ring.

[0012] To achieve the best seal with the threaded plug, it is preferred that the flange and the sealing ring have corresponding sizes, that is have sizes so that they may cover each other.

[0013] In a preferred embodiment of the threaded plug with a sealing ring, the sealing ring has a thickening on at least the one face, and, preferably, the sealing ring has thickenings on both of the opposed faces. The thickening may contribute to sealing against liquids which penetrate inwards below the threaded plug from the surroundings, e.g. paint, lacquer or the like, which may seep inwards below the flange and the sealing ring and make it difficult to loosen the threaded plug, when this should be desired.

[0014] To achieve the best seal against penetrating liquids, it is preferred that the thickening or thickenings extend essentially in a ring-shaped manner and preferably along the entire outer periphery of the sealing ring. Hereby, a good seal along the periphery of the threaded plug may be achieved, which is also capable of preventing liquids from seeping inwards below the flange and the sealing ring. In principle, the thickenings are a local area of the sealing ring, where the thickness of material has been made larger so that the sealing ring is thicker in this area.

[0015] Of course, it is possible to provide embodiments of the sealing ring where it has several such thickenings, which may be disposed like rings inside one another on the faces of the sealing ring.

[0016] Since the sealing ring is mounted loosely on the threaded plug, it is advantageous that the sealing ring comprises means for holding it on the threaded plug. The means may e.g. be projections in the central opening of the sealing ring, which are capable of applying pressure to the threaded plug and thereby of holding the sealing ring substantially fixed on the threaded plug.

[0017] Alternatively, the threaded plug may comprise means for holding the sealing ring. The means for holding the sealing ring may be protuberances, jaws, projections or grooves. This means that the threaded plug may be provided with protuberances or jaws on its surface which, in pairs, protrude and grip the sealing ring. In the area adjoining the flange where the sealing ring is disposed, the threaded plug may be provided with several such pairs of protuberances or jaws arranged in a circumference on the threaded plug with a distance between them. For instance, 4, 6 or 8 pairs of protuberances or jaws may be arranged on the threaded plug.

[0018] In some embodiments, the sealing ring may be configured so that it is suited for engagement with the protuberances or the jaws. For instance, it may be made thinner in the area toward the central opening, so that it may be fitted in the space between the protuberances or the jaws.

[0019] It is also possible to hold the sealing ring on the threaded plug by locally increasing the diameter of the threaded plug. It will typically be an area of the threaded part which adjoins the flange. Such a solution, like the use of protuberances, jaws or the like, may also serve to centre the sealing ring on the threaded plug.

[0020] The threaded plug may be made of metal or plastics or optionally of ceramics. Metal may e.g. be iron, brass, stainless steel or aluminium. Preferably, the threaded plug is injection moulded in a plastics material, such as e.g. polyamide or PEHD. The sealing ring is generally made of a thermoplastics material which is flexible in use, e.g. TPE, rubber or nitrile rubber. The sealing ring may be made of all materials which are suitable for use in gasket, Both the threaded plug and the sealing ring may be fibre-reinforced.

The drawing

[0021] The invention will now be explained more fully with reference to a drawing, in which

figure 1

shows an embodiment of the threaded plug with sealing ring according to the invention,

figure 2

shows a section of the threaded plug of figure 1,

figure 3

shows the threaded plug in perspective,

figure 4

shows another embodiment of the threaded plug with sealing ring according to the invention,

figure 5

shows a section of the threaded plug of figure 4, and

figure 6

shows the threaded plug of figure 4 in perspective.

Descriction of the exemplary embodiments

[0022] Figure 1 shows a threaded plug 1 with a head 2 and a threaded part 3. The threaded plug 1 is provided with a sealing ring 4 which is disposed in connection with the flange 5. The flange 5 is provided with a projection 6 on the face which faces toward the sealing ring 4.

[0023] In this embodiment, the threaded plug is provided with protuberances or jaws 7 for holding the sealing ring 4 on the threaded plug 1.

[0024] The jaws 7 will be seen better in figure 2, which is a section of figure 1. It will be seen here that the jaws 7 are disposed in extension of the threaded part 3 just below the flange 5, so that the sealing ring 4 engages the flange 5. The projection 6 on the face of the flange 5 is also shown clearly in figure 2.

[0025] It will also be seen in figure 2 that an area 4a of the sealing ring 4, which is in engagement with the jaws 7, is configured so as to fit in the jaws.

[0026] Figure 3 is a perspective drawing, which shows the threaded plug 1 with the head 2 and the threaded part 3 with the sealing ring 4 mounted in connection with the flange 5.

[0027] Figure 4 shows an alternative embodiment of a threaded plug 10 according to the invention with a head 12 and a threaded part 13. The threaded plug 10 is provided with a sealing ring 14 which is disposed in connection with the flange 15. The flange 15 is provided with a projection 16 on the face which faces toward the sealing ring 14.

[0028] In this embodiment, the sealing ring 14 has thickenings 18 on both of its opposed faces. The thickenings 18 are shown more clearly in figure 5, which is a section of figure 4. The thickenings 18 are provided in the outer periphery of the sealing 14. This means that when the threaded plug 10 is used for closing an opening, the flange 15, upon tightening, will press down against the sealing ring 14 and the thickenings 18 and hereby cause an extra good seal along the outer rim of the flange 15, so that paint or the like, which is applied subsequently, does not penetrate inward below the flange 15.

[0029] As will be seen in figure 6, the sealing ring 14 is held on the threaded plug 10 in this case by means of a plurality of projections 19 in the central opening of the sealing ring 14. The projections 19 press against the threaded plug and hold the sealing ring 14 in its position against the flange 15.

Claims

1. A threaded plug with a sealing ring, said threaded plug comprising a head and a threaded part, wherein a flange is provided between the head and the threaded part to cooperate with the sealing ring, which is mounted on the side of the flange which faces toward the threaded part, characterized in that the flange (5, 15) is provided with a projection (6, 16) having a tapered cross-sectional shape, which extends continuously on the entire face of the flange (5, 15) which faces toward the sealing ring (4, 14).

2. A threaded plug with a sealing ring according to claim 1, characterized in that the projection (6, 16) extends in a substantially circular shape.

3. A threaded plug with a sealing ring according to claims 1 and 2, characterized in that the flange (5, 15) and the sealing ring (4, 14) have the same extent.

4. A threaded plug with a sealing ring according to any one of the preceding claims, characterized in that the sealing ring (14) has a thickening (18) on at least the one face.

5. A threaded plug with a sealing ring according to claim 4, characterized in that the thickening (16) extends essentially in a ring shape and preferably along the outer periphery of the sealing ring (14).

6. A threaded plug with a sealing ring according to any one of the preceding claims, characterized in that the sealing ring (4, 14) comprises means in the form of one or more inwardly facing projections (7, 19) for holding the sealing ring to the threaded plug (1, 10),

Drawing