Technical Field Technical Field

[1] The present invention regards a handle for submersible pumps and the like.

Background Art Background Art

[2] It is known that in order to empty wells, underground rooms, tanks or other types of similar reservoirs, pumping members, such as in particular submersible pumps, are generally used for domestic, civil and industrial purposes. Submersible pumps of the prior art generally provide for a lower support base, a delivery body associated at the upper part to the support base, arranged inside which is a rotor member in communication with an external environment, a generally cylindrical motor body, adapted to house a motor member, and a covering cap adapted to close the motor body at the upper part. Usually, the covering cap is provided with a gripping member or handle to facilitate the gripping of the submersible pump, in such a manner to make lifting and transfer thereof easier.

[3] An example of a submersible pump of the known type is illustrated by the patent n ⁰

US 5,207,562. The described submersible pump is provided with a particular handle adapted to incorporate a passage channel for the electrical power supply cables of the motor member therein, as well as a passage gap for the introduction of lubrication oil and coolant into the motor body.

[4] Another example of a submersible pump of the prior art is provided by the European patent application EP 1887226 A2 which illustrates a submersible pump comprising means for switching on and switching off connected to liquid level sensor means to be transferred, arranged in such a manner to detect the presence of liquid and control the switching on and switching off of the pump depending on the detected liquid level. Such sensor means are deformable in such a manner to activate the means for switching on and switching off at a determined deformed configuration.

[5] In the submersible pumps of the prior art there is the particular need of simultaneously ensuring a perfect mechanical seal at the connection between the covering cap and the motor body and a complete reliability of the mechanical resistance of the handle adapted to allow transferring and lifting the pump itself. In order to meet such needs, the submersible pumps of the prior art combine the use of generally complex and expensive fixing and sealing means.

[6] Furthermore, the submersible pumps in question require frequent maintenance op- erations, to remove the particles that are inevitably carried by the liquid transferred by the pump. Thus, the presence of complex fixing components does not facilitate a quick performance of such operations, making the submersible pumps of the prior art poorly satisfactory also from this point of view. Disclosure of Invention Disclosure

[7] The task of the present invention is that of overcoming the aforementioned drawbacks, by providing a handle adapted to be associated in a reliable and safe manner to submersible pumps and the like.

[8] Within the scope of such task, another object of the present invention is that of providing a handle for submersible pumps and the like which can be mounted and dismounted in an easy and quick manner.

[9] Another object of the invention is that of providing a handle for submersible pumps that is easy to manufacture, versatile in use and safe, as well as relatively inexpensive.

[10] The abovementioned objects are attained, according to the present invention, by the handle for submersible pumps according to claim 1. Description of Drawings

[11] The details of the invention shall be more apparent from the detailed description of a preferred embodiment of the handle for submersible pumps, illustrated for indicative purposes in the attached drawings, wherein:

[12] figure 1 shows a longitudinal section view of a submersible pump provided with the handle according to the present invention;

[13] figure 2 shows a perspective view of a closing unit of the same submersible pump;

[14] figure 3 shows a plan view of the closing unit of the pump illustrated in figure 3;

[15] figure 4 and figure 5 show axial sectional views of the same closing unit respectively according to planes IV-IV and V-V of figure 3. Best Mode

[16] With special reference to such figures, a pump of the submersible type provided with the handle 2 according to the invention is indicated in its entirety with 1. The pump 1 comprises a support base 3, a delivery body 4 connected - at the upper part - to the support base 3 and adapted to accommodate the rotor member therein intended to transfer a liquid in which the pump 1 is submerged at least partially. In particular, at the connection portion between the delivery body 4 and the support base 3, the pump 1 provides for an open central section for the inlet of the liquid to be transferred. The delivery body 4 also provides for a peripheral inflow section 5 for the out flow of the liquid transferred by the rotor member. Provided for at the upper part of the delivery body 4 is a motor body 6 preferably made up of a cylindrical casing adapted to house an electrical motor therein for the actuation of the abovementioned rotor member. In particular, the motor body 6 is preferably arranged, just like the motor and the rotor member, with vertical longitudinal axis.

[17] Provided for covering the motor body 6 is an upper closing unit 7 applied to which is the handle 2. The closing unit 7 comprises a substantially cylindrical- shaped external cap 8 adapted to be sealingly connected to the motor body 6. Preferably, the external cap 8 is adapted to close - at the upper part - the motor body 6 by interposing mechanical seal means. For example, provided for may be annular- shaped sealing means, prearranged at a suitable seat obtained at the upper edge of the motor body 6 adapted to be coupled to the lower edge 9 of the external cap 8.

[18] Furthermore, the external cap 8 provides for a pair of openings 10 arranged at the top, for the respective engagement of cable-holder units 11. The cable-holder units 11 are made up of respective sleeves adapted to allow the passage of electrical power supply cables of the motor member connected to the rotor member.

[19] The closing unit 7 further comprises a first and a second internal cap 12, 13, adapted to be inserted inside the external cap 8 at the top of the latter. The first and the second internal cap 12, 13 are respectively provided with passage openings 14, 15 at the openings 10 of the external cap 8, for the passage of the borne electrical cables that pass through, in use, the abovementioned cable-holder units 11. More precisely, the second internal cap 13 is arranged, in use, facing the internal top of the external cap 8. On the contrary, the first internal cap 12 is arranged, in use, associated integral with the internal cap 13, for example through coupling - using screw fixing means - to the motor body 6, and on the inner side it faces the chamber intended to house the electrical connections and the possible capacitor in cases where the installed motor is of the single-phase type. Such chamber is closed at the top of the motor body 6 by a respective further cap 12a (see figure 5).

[20] The second internal cap 13 forms an open central embossment 17, threaded internally, intended to be engaged axially by a threaded cork 18, as better outlined hereinafter. The central embossment 17 of the second internal cap 13 is housed, during use, inside a corresponding shaped seat 19 of the first internal cap 12. Made on the bottom of such shaped seat 19 is a perforation 16 coaxial to the abovementioned central embossment 17.

[21] The external cap 8 centrally forms an embossed portion 20, shaped in such a manner to at least partially engage the described central embossment 17. In particular, the embossed portion 20 forms - at the lower part - a centrally perforated flat seat 21 for the insertion of the abovementioned cork 18. Preferably, the cork 18 is adapted to engage the perforated flat seat 21 by interposing seal means 22, so as to connect in a watertight manner, through threaded coupling with the central embossment 17, the external cap 8 to the second internal cap 13.

[22] The handle 2 is adapted to be preferably applied to the external top of the described closing unit 7. More precisely, the handle 2 comprises a body 24 adapted to be associated to the top of the closing unit 7 by interposing a fixing group 23 housed inside the body 24 itself.

[23] The body 24 of the handle 2 comprises a lower tubular portion 25, adapted to house a clamping unit 23, and fit onto the closing unit 7, and an upper portion bearing a pair of arms 26 opposite to the central top of the body 24, to allow the gripping of the pump 1. The arms 26 develop from the central part of the body 24 (see in particular figures 2 and 3).

[24] The clamping unit 23 substantially comprises a clamping member 28, adapted to engage elastic connection means 27 borne by the body 24 inside the tubular portion 25, and drive means 36 adapted to perform an axial translation of the clamping member 28 to generate radial elastic expansion of the abovementioned elastic connection means 27 against a contrasting portion 29 integral with the closing unit 7 of the pump 1, in such a manner to achieve mutual blocking between the body 24 of the handle 2 and the same pump 1.

[25] The elastic connection means 27 are preferably made up of a crown-shaped appendix, shaped axially by the body 24 itself inside the tubular portion 25. The crown 27 peripherally has a plurality of longitudinal notches 30.

[26] The clamping member 28 preferably comprises a mushroom-shaped element, perforated axially, made up of a central stem 31, facing - in use - the crown 27, and an operational head 32. In particular, the operational head 32 has a lateral operational surface 33 with a configuration diverging in the axial direction of the stem 31 towards the end, in such a manner to define a smaller base adjacent to the stem 31 and a larger end base. In the illustrated case, for example, the operational head 32 is frustoconical- shaped.

[27] It should be observed that the smaller base of the operational head 32 has transverse dimensions such to internally engage the crown 27. In order to facilitate the insertion of the operational head 32 in use, the crown 27 may have - at the end edge - a suitable tapered element. The operational surface 33 of the mushroom- shaped element 28 also has a plurality of longitudinal ribs, not represented for the sake of simplicity, suitable to engage the longitudinal notches 30 of the crown 27, to prevent the rotation of the mushroom- shaped element 28 and allow only the translation thereof.

[28] At the larger base, the operational head 32 preferably configures a cavity 34 shaped in such a manner to house, in use, the head of the cork 18. The stem 31 on the other hand is adapted to be arranged, in an operational clamping condition better described hereinafter, abutting against a flat seat 35 obtained axially inside the body 24. [29] The body 24 also has an axial perforation to allow the insertion of screw means forming the abovementioned drive means 36 and adapted to engage, with a threaded end portion, the mushroom-shaped element 28 at the respective axial perforation. More precisely, the screw means 36 comprise a head adapted to be housed in a respective seat at the top of the body 24 by interposing a special blocking washer 36a.

[30] The contrasting portion 29 is preferably made up of a cap-shaped element bearing - at the upper part - a containment collar 37, shaped in such a manner to contain the crown 27. In particular the collar 37 has an internal wall shaped converging from the open end base, such to define a longitudinal profile joined to the operational surface 33 of the mushroom-shaped element 28 at the interposition, in use, of the crown 27. In the illustrated case the collar 37 is frustoconical- shaped.

[31] The cap-shaped element 29 is adapted to be overlapped and connected through known fixing means to the external cap 8. In order to facilitate its positioning, in use, inside the body 24, the body 24 itself may have an annular seat 38 at the base of the crown 27, to house the edge of the open portion 37 when the handle 2 is completely clamped to the closing unit 7.

[32] The operation of the handle for submersible pumps and the like is described hereinafter.

[33] In a mounting step, in which the closing unit 7 is prearranged, the first internal cap

12, the second internal cap 13 and the further cap 12a are mutually fastened through screw fixing means 39 of the known type to the motor body 6, in such a manner that the perforated flat seat 21, the central embossment 17 and the perforation 16 are aligned axially.

[34] In a successive step, the cable-holders units 11 for connection to the electrical power supply means may be sealingly fixed in the respective openings 10.

[35] Subsequently, the seal means 22, upon inserting the cork 18 in the central embossment 17 are interposed and the clamping is performed through threaded coupling. The cork 18 therefore sealingly closes the top of the external cap 8 and simultaneously provides connection between the internal caps 12, 13 already mutually clamped, and the external cap 8. At this point, a no-load test is carried out. For such purpose the cork 18 may have a threaded axial hole adapted to be closed by means of a screw 18a with the interposition of a seal ring. A further screw connection 18b may be analogously provided at the upper part of the closing unit 7.

[36] At this point the preassembly of the mushroom-shaped element 28, the body 24 and the drive means 36 comprising a blocking washer 36a is carried out. The drive means 36 are partially started.

[37] Subsequently, the group thus assembled is overlapped to the external cap 8, in such a manner that the collar 37 is centred axially with respect to the mushroom- shaped element 28.

[38] In a first clamping step, the threaded stem of the screw means 36 progressively engages the axial perforation of the mushroom- shaped element 28, until the head of the screw means 36 abuts in a respective housing seat obtained at the top of the handle 2. Already in this step, the ribs present on the operational surface 33 engage the longitudinal notches 30 of the crown 27, blocking the rotation of the mushroom-shaped element 28 and thus allowing the progressive insertion of the screw means 36.

[39] When the head of the screw means 36 achieves abutment, the further rotation of the same means causes the axial movement of the mushroom-shaped element 28, which thus moves closer towards the crown 27. Due to the frustoconical configuration of the mushroom- shaped element 28, the axial movement of the same is suitable to cause the progressive elastic radial expansion of the crown 27. Such expansion is blocked, in a condition of complete clamping, by the containment action provided by the collar 37 of the cap-shaped element 29. Therefore, upon completing clamping, the crown 27 is elastically deformed and compressed by the mushroom-shaped element 28 against the internal frustoconical wall of the collar 37, obtaining a safe and reliable connection of the handle 2 against closing unit 7.

[40] Therefore, the handle according to the invention attains the object of ensuring a reliable and safe application to submersible pumps and the like.

[41] Such result is attained in particular due to the radial expansion of the crown 27 made of plastic material operated by means of the clamping unit 23. Such expansion, made possible by the material as well as by the particular geometry of the crown 27, such to allow deflection deformations, safely determines the clamping of the crown 27 itself and thus the body 24 against the inner wall of the collar 37 of the cap-shaped element 29.

[42] The sealing is instead mainly obtained by the cork 18 adapted to be clamped by interposing suitable seal means to the external cap 8 and to the first internal cap 12, to the second internal cap 13 and to the further cap 12a. The sealing is ensured in combination with the connection means 18a and 18b, at the cable-holder opening 10 and through annular- shaped seal means prearranged at the upper edge of the motor body 6, as described previously.

[43] A characteristic of the invention consists in the fact that the clamping is guaranteed under any condition and precision degree of the mechanical components of the described clamping unit 23. As a matter of fact, the abovementioned radial expansion is efficient even in cases where the collar 37 of the cap-shaped element 29 is not perfectly coupled to the operational surface 33 of the mushroom- shaped element 28. It should also be observed that the radial expansion clamping according to the invention allows an easy mounting of the mechanical closing parts. [44] A further aspect of the invention consists in the fact that the claimed expansion clamping is obtained using very few mechanical pieces, whose dimensional precision has a lower impact on the efficiency of the closure, which is however guaranteed by the elastic behaviour of the crown 27.

[45] Another advantage of the handle subject of the invention is that of being easy to mount and dismount. In particular, the mounting of the clamping unit 23 occurs by rotating the screw means 36, in the direction adapted to move the mushroom- shaped element 28 away from the crown 27, in such a manner to determine the elastic return from the radial expansion condition, releasing the same crown 27 from the internal wall of the collar 37.

[46] In practice, the embodiment of the invention, the materials used, as well as the shape and dimensions, may vary depending on the requirements.

[47] Should the technical characteristics mentioned in each claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding the claims and hence they shall not be deemed restrictive in any manner whatsoever on the scope of each element identified for exemplifying purposes by such reference signs.