TECHNICAL FIELD The present invention relates to a water drain siphon device, in particular for floor showers and shower trays .

BACKGROUND ART

Various types of water drain siphon devices are known: in any case, these variously shaped devices generally comprise a siphon portion, which typically consists of a conveniently folded tube or is obtained within a containing case which accommodates conveniently arranged partitions. In all cases, the siphon portion defines a water seal between ^' the environment where the device is installed and the draining tube to which the device is connected.

Water seal commonly means a conduit portion shaped so as to define a water stagnation zone which is interposed between conduit lengths placed upstream and downstream of the water seal, and completely obstructs the passage section of the conduit to prevent the air from passing, thus excluding backflows and odor return towards the users . For the devices of this type to be fully effective, they should have certain constructional features and certain dimensions, which however make them relatively cumbersome, in general, especially along their height (vertical direction) , and/or complex to be manufactured and installed. Several known devices are shaped so as not to be completely satisfactory, for example, when used with floor showers and shower trays, where restraining the height of the device is essential, on one hand for obtaining an aesthetic effect particularly appreciated by the users, and on the other hand, for avoiding the floor on which the shower is installed from being broken, during the installation, to accommodate the drain device .

An example of drain device having a water seal is shown in DEl02006058259Al, having a generally flattened shape and being thus appropriate for replacing the traditional siphons in which the tube is shaped to display sharp curves.

However, the device disclosed in this patent application is also not free from drawbacks, as well as others which are more or less similar, particularly in terms of efficiency, manufacturing simplicity, volumes . DISCLOSURE OF INVENTION

It is an object of the present invention to provide a water drain siphon device, in particular for floor showers and shower trays, but non only, which is highly simple and cost-effective to be implemented and fully effective while being very small in size, thus being particularly suitable to be used in showers .

Hence, the present invention relates to a water drain siphon device, in particular for floor showers and shower trays, as defined in the appended claim 1.

The water drain siphon device in accordance with the invention is highly simple and cost-effective to be implemented and fully effective while being very small in size, thus being particularly suitable to be installed beneath a shower tray (even if it may obviously have other applications) .

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further described in the following non-limiting embodiments, with reference to the accompanying drawings, in which:

- figure 1 is an exploded perspective view of a water drain siphon device in accordance with the invention;

- figure 2 is a longitudinal section view of the device in figure 1 being assembled;

- figure 3 is a top plan view of the device in figure 1, with parts removed for clarity;

- figure 4 is a longitudinal section view of a variant of the device of the invention; - figure 5 is a partial perspective view of a further variant of the device of the invention. BEST MODE FOR CARRYING OUT THE INVENTION With reference to figures 1-3, a water drain siphon device 1 comprises a plastic hollow main body 2, which has a tub 3 provided with a top inlet opening 4 and a conduit 5 which laterally projects from tub 3 and extends along an axis A; an essentially annular cover 6, attachable to a peripheral edge 7 of inlet opening 4 and supporting a grid 8 (or another similar outer closure element) on the outside of tub 3; and a conveyor element 9, housed inside tub 3 and coupled to a radially inner collar portion 11, e.g. substantially cylindrical, of cover 6.

According to the preferred embodiment shown in figures 1-3, body 2, formed by tub 3 and conduit 5, is a monolithic hollow body made of plastic, in particular of thermoplastic material; conduit 5 is integrally obtained with tub 3 to form such a monolithic body.

Conduit 5 comprises, and preferably consists of, a flattened tube element 10 which is wavy along axis A, the width thereof being greater than the height in cross section, and preferably twice the height; the inner cross section of tube element 10 is preferably (but not necessarily) substantially rectangular with rounded corners . Body 2 is delimited by two opposed lateral sides 13 and by an upper wall 14, provided with inlet opening 4, and a lower wall 15 facing each other. Body 2 further has an end wall 16 joining sides 13 and axially closing a longitudinal end 17 of body 2.

Upper wall 14 and lower wall 15 ha-ve respective flat portions 18, 19 and respective wavy portions 20, 21, the wavy portions of one wall facing the flat portions of the opposite wall.

In particular, from end 17 and beyond inlet opening 4, upper wall 14 has a first upper flat portion 18a and a second upper flat portion 18b, connected to each other by means of an upper wavy portion 20; from end 17, lower wall 15 has a first lower flat portion 19a, a first lower wavy portion 21a, a second lower flat portion 19b and a second lower wavy portion 21b. Wavy portions 20, 21 are, for example, substantially V-shaped with a rounded vertex.

The width of body 2, intended as the distance between sides 13, is greater (in particular, at least twice) than the height of body 2, intended as the vertical distance between upper wall 14 and lower wall

15, or more precisely, between two parallel planes lying on flat portions 18 of upper wall 15 and on flat portions 19 of lower wall 14.

Tub 3 is delimited by a lateral wall 23 which consists of the end portions of sides 13 and of end wall

16, and by a bottom wall 24 consisting of lower flat portion 19a and facing inlet opening 4; tub 3 communicates with conduit 5 through a lateral passage opening 25 substantially orthogonal to axis A.

Tub 3 carries cover 6 and houses conveyor element 9.

Cover 6, which is advantageously made of thermoplastic material too, is attached to peripheral edge 7 of inlet opening 4 by, for example, heat sealing. In the example shown in figures 1-2, cover 6 comprises a substantially cylindrical, inner collar 26 defining radially inner collar portion 11 of cover 6, and a radially outer flange 27 which projects from an upper end of collar 26 and is coupled to peripheral edge 7. Flange 27 carries a support 28 for grid 8, e.g. a frame. Element 9 is inserted into portion 11, which is connected to peripheral edge 7 of inlet opening 4 and projects into tub 3. Element 9 is telescopically coupled to cover 6, namely to portion 11, element 9 being slidingly inserted into portion 11 so as to be orthogonal to inlet opening 4.

Element 9, which is preferably made of thermoplastic material, is slidably inserted inside cover 6 up to inferiorly rest against bottom wall 24 of tub 3; element 9 is substantially tube-shaped, e.g. cylindrical, and has a coupling portion 29, a baffle 30 provided with one or more auxiliary openings 31 facing passage opening 25, and support portions 32.

Coupling portion 29 optionally carries a substantially annular, elastic radial seal 33 (e.g. CD- ring type) and is coupled to collar 26 (i.e. to portion 11) of cover 6 by an interference fit and in a fluidtight manner; seal 33 is radially interposed between element 9 and portion 11.

Baffle 30 faces passage opening 25 and projects from coupling portion 29 towards bottom wall 24 of tub 3; auxiliary opening 31 facing passage opening 25 is defined, for example, by the gap between a lower edge 34 of baffle 29 and bottom wall 24. Support portion 32 consists of one or more pins circumferentially spaced apart from one another, for example, and resting against bottom wall 24.

Baffle 30 forms an upper partition 36 which projects downwards (i.e. towards lower wall 15) from upper wall 14 and defines a first water seal 41 within body 2, along with a lower partition 37 consisting of wavy portion 21a, that projects upwards (i.e. towards upper wall 14) from lower wall 15 and is axially spaced apart from upper partition 36.

In accordance with the invention, at least a second water seal 42 is arranged within body 2 and arranged in series with first water seal 41 along axis A; second water seal 42 is also defined between an upper partition 46 and a lower partition 47, opposed and axially spaced apart from each other; in this case, as well as lower partition 37 is defined by curved portion 21a-of lower wall 15, for example substantially V-shaped with a rounded vertex, which vertically projects towards flat portion 18a of upper wall 14, lower partition 47 is defined by curved portion 21b of lower wall 15, for example substantially V-shaped with a rounded vertex, which vertically projects towards flat portion 18b of upper wall 14.

Upper partition 46 is interposed between lower partitions 37, 47, in this case consisting of curved potion 20 of upper wall 14 which is, in turn, substantially shaped as a V with a rounded vertex, and projecting towards lower wall 15.

Lower partition 37 which is closer to tub 3 (or to end 17 of body 2) than lower partition 47 and defines first water seal 41 is higher than lower partition 47 defining second water seal 42; in other terms, first water seal 41, that is closer to tub 3, is higher than second water seal 42, that is farther from tub 3.

Lower partitions 37, 47 end with respective upper edges 48, 49 placed at predetermined distances from upper wall 14, so as to define respective passage sections (orthogonal to the axis) above lower partitions 37, 47. Both lower edge 34 of baffle 30 defining upper partition 36 and a lower edge 50 of upper partition 47 are arranged beneath upper edges 48, 49 of lower partitions 37, 47.

The passage section (orthogonal to the axis) of tube element 10 at lower partition 37 of first water seal 41 closer to tub 3, is smaller than all subsequent passage sections of tube element 10.

Auxiliary opening 31 is entirely arranged beneath the passage section placed at first water seal 41 (i.e. at lower partition 37 which defines first water seal 41) .

Conduit 5 further comprises a substantially circular cross section end tube 51, joined to tube element 10 via a joint portion 52 converging towards tube 51 in a horizontal plane, and diverging towards tube 51 in a vertical plane. In particular, joint portion 52 has two lateral sides 53 joined to sides 13 and converging towards tube 51, and an upper wall 54 and a lower wall 55 joined to upper wall 14 and to lower wall 15, respectively, diverging towards tube 51.

Joint portion 52 between tube element 10 and tube 51 has a inlet section which is greater than the outlet section.

Tube 51 is arranged in a vertically higher position with respect to a horizontal plane defined by bottom wall 24 of tub 3, i.e. to the plane passing on flat portions 19 of lower wall 15.

According to one aspect of the invention, conveyor element 9 is removable from tub 3 and first water seal

41 which is closer to tub 3 is shaped so as to be accessible by a user's hand through inlet opening 4 once element 9 has been removed.

According to a further aspect of the invention and with reference also to figure 4 , where similar or like details to those already described are denoted by the same numerals, at least two interchangeable covers 6 are provided: a first cover 6a (shown in figures 1-2) is provided with support 28 on which a grid 8 is fittable, which grid is selected from a plurality of different interchangeable grids; a second cover 6b (shown in figure 4) is provided with a threaded portion 56 to be coupled to an outer closure element 57, having a cylindrical portion 58, for example, closed at the top by a plug 59 provided with draining openings. Cover 6b is also advantageously made of thermoplastic material and is attached to peripheral edge 7 of inlet opening 4 by heat sealing, for example.

In the example in figure 4, cover 6b comprises a substantially cylindrical, inner collar 26 and a radially outer flange 27 which projects from an upper end of collar 26 and is coupled to peripheral edge 7. Collar 26 internally carries threaded portion 56 which cooperates with an outer threaded portion 60 of closure element 57. Thereby, the distance between cover 6b (specifically plug 59) and bottom wall 24 of tub 3 (i.e. lower wall 15 of body 2) may be varied. The previously described conveyor element 9 is still inserted so as to slide in a collar portion 11, connected to peripheral edge 7 of inlet opening 4 and projecting into tub 3; in this case, collar portion 11 is formed by two pieces telescopically coupled to each other, here consisting of collar 26 and cylindrical portion 58, respectively, joined together by means of a threaded coupling defined by threaded portions 56, 60; again, element 9 is coupled to portion 11 by an interference fit and in a fluidtight manner, optionally by means of an annular radial seal 33, namely to a lower length of cylindrical portion 58. Flange 27 is optionally coupled to a seal 61. Main body 2 is shaped so as the height of main body 2, measured between a resting plane of device 1 (i.e. of lower wall 15) and peripheral edge 7, is smaller or equal to about 60 mm, and preferably smaller or equal to about 55 mm, the diameter of end tube 51 being of about 50 mm (a common diameter for these applications); due to the particular shape of body 2, device 1 has an overall height (including grid 8 or closure element 57) smaller than 65 mm and however passes the following tests: - "Water Seal" as per point 5, EN1253-2 standard;

- "Hydraulic Requirements" as per point 4.6, EN274 standard;

- "Size" G, Z, a, H, h, C as per EN274 standard for shower trays D.90.

In the variation in figure 5, where similar or like details to those already described are denoted by the same numerals, body 2 still has the previously described, general construction but also has link portions 62 integrally obtained with body 2 and radially projecting from lateral wall 23 of tub 3 to be connected to respective additional conduits (non shown) channeling water to device 1 (specifically to tub 3) .

It is understood that further changes and variations may be made to the device described and illustrated herein, without departing from the scope of the appended claims.

According to a variation (not shown) , for example, device 1 comprises a tub 3 from which laterally project two or more conduits 5.

As described above, this variant may be carried out by molding a monolithic body 2 which comprises both the tub and all conduits 5; or several bodies 2 may be more advantageously used, exactly as described above, each thus having a tub 3 and one lateral conduit 5 ; bodies 2 are then cut along respective diameters of respective tubs 3, for example, and then joined to one another along the cut edges of tubs 3 (e.g. by heat sealing) .