The present invention concerns an electropump for moving liquid substances, usable in washing apparatuses, or in domestic appliances that recirculate liquids, but not only, of the domestic or commercial type.

Electropumps are known, usable in washing apparatuses of the domestic or commercial type, driven electrically, comprising an impeller located during use at least partly immersed in a liquid substance; such pumps are intended to operate in washing machines, dishwashers, glass washers or suchlike.

Known electropumps comprise a rotation shaft, on which the impeller is applied, which cooperates with a drive member, in particular with the rotor of the latter, to make it rotate.

Generally, known electropumps of the type described above comprise a containing body configured to contain the motor and the impeller. The containing body normally consists of two individual bodies, structurally connectable, of which one contains and positions the drive member and the other contains and positions the impeller.

The shapes and connections of the two bodies are extremely varied. The present invention concerns the body that contains the impeller, normally consisting of a pump body and an introduction body. The shaft connects rotatably to the pump body, either only through a sealing gasket, or also with a bench bearing.

The invention concerns in particular the pump body, that is, the body that separates the impeller from the drive member, through which passes the shaft that makes the impeller rotate, which can include only the gasket or also the bench bearing, depending on the type of assembly.

One disadvantage of known electropumps to which the invention refers is that the sealing elements do not guarantee a sufficient protection for the bearing and/or the electric part from possible infiltrations of liquid substances, especially after a certain period of use.

In particular, in the event of possible damage or wear to the sealing element, the liquid substance leaks and flows along the rotation shaft toward the bearing and sometimes as far as the motor. This can cause damage to the bearing and/or motor, and hence the need for maintenance and/or replacement thereof.

Document US-A-2005/0158195 concerns an electropump for the circulation of fluids comprising a drive member disposed in a housing of the motor, which has a pump body mounted on one end. The pump body supports a support element for a drive shaft connected on one side to the drive member and on the other side to an impeller disposed in a chamber defined by the pump body and by an introduction element. The pump body also supports multiple sealing components to limit leakages of liquid from the chamber along the drive shaft.

One purpose of the present invention is to provide an electropump, for domestic or commercial use, that is simple and reliable in terms of its hydraulic seal.

Another purpose is to provide an electropump suitable to protect the bearing and/or the motor from possible drops and infiltrations of liquid, even if the sealing element is worn and/or damaged.

Another purpose of the present invention is to provide an electropump that is simple and economical to make, and that reduces problems of maintenance and reactivation.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, an electropump for domestic or commercial purposes comprises an impeller associated with a rotation shaft which cooperates with a drive member.

The electropump comprises an impeller body, in which the impeller is positioned, comprising in its turn a pump body, which separates the impeller from the drive member.

The pump body comprises a support portion provided with a through hole through which the rotation shaft is positioned, and a positioning seating in which a hydraulic seal device can be positioned, in order to at least reduce, or possibly prevent completely, leakages of liquid from the body of the impeller toward the drive member.

The positioning seating for the hydraulic seal device is disposed on the side which, during use, faces toward the impeller.

According to some embodiments, the support portion is provided with a housing seating, opposite the positioning seating, in which a support element of the rotation shaft can be positioned.

According to one aspect of the present invention, the support portion is provided with discharge means located between the hydraulic seal device and the drive member.

The discharge means, in the presence of a support element of the rotation shaft, are advantageously located before the support element. In particular, the discharge means are located between the seal device and a housing seating in which the support element is positioned.

According to some embodiments, the housing seating is present in the support portion on the side facing toward the drive member.

According to some embodiments, the discharge means comprise at least one discharge groove, advantageously two, three or more.

According to some embodiments, at least one portion of the at least one groove is located in the support portion.

According to some embodiments, the discharge grooves are disposed radially with respect to the through hole and are made so that the drops of liquid that have possibly leaked are diverted toward the surface of the support body facing toward the drive member.

According to possible solutions, as we said, two or more discharge grooves can be provided, to guarantee discharge in any work condition of the electropump.

According to variant embodiments, a hydraulic seal device is provided, disposed between the impeller and the body of the impeller, and configured to prevent the liquid from leaking through the through hole toward the drive member.

According to other variant embodiments, a seal body is positioned in the housing seating, configured to perform an anti-vibration function between the housing seating and the support element for the rotation shaft.

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

• fig. 1 is a schematic view in perspective of an electropump in accordance with embodiments described here;
• fig. 2 is a perspective view of the pump body of an electropump in accordance with embodiments described here,
• fig. 3 is a view along the section plane π in fig. 1 in accordance with embodiments described here;
• fig. 4 is a view along the section plane π in fig. 1 in accordance with variant embodiments described here;

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

We shall now refer in detail to the various embodiments of the present invention, of which one or more examples are shown in the attached drawing. Each example is supplied by way of illustration of the invention and shall not be understood as a limitation thereof. For example, the characteristics shown or described insomuch as they are part of one embodiment can be adopted on, or in association with, other embodiments to produce another embodiment. It is understood that the present invention shall include all such modifications and variants.

Embodiments described here concern a pumping device 10 for liquids, usable in washing apparatuses, or in domestic appliances that recirculate liquids, such as washing machines, dishwashers or suchlike, for pumping liquid substances.

The pumping device 10 comprises an impeller 12, located during use in contact with the liquids to be pumped, and a rotation shaft 14 on which the impeller 12 is installed.

The pumping device 10 also comprises a drive member 16, in particular an electric motor, connected to the rotation shaft 14 and configured to make the shaft 14 rotate.

According to some embodiments, the drive member 16 comprises a fixed stator part 17 and a rotor part 18 rotating with respect to the stator part 17.

The rotor part 18 can be keyed onto the rotation shaft 14 to make it rotate by interaction with the stator part 17.

According to some embodiments, the drive member 16 can also comprise a cooling fan 19, to cool the drive member 16.

According to possible solutions, the drive member 16 is enclosed at the rear, that is, in the part opposite the impeller 12, by a rear cap 20. According to possible solutions, the rear cap 20 can extend so as to at least partly surround the lateral surface of the drive member 16.

The rear cap 20 can be provided with a seating 21 in which a first support element 22 can be positioned, to support the rotation shaft 14.

According to some embodiments, the support element 22 can be a bearing.

The pumping device 10 also comprises an impeller body 24 in which the impeller 12 is positioned.

The impeller body 24 separates the impeller 12 from the drive member 16; moreover, the impeller body 24 is provided with a through hole 25 through which the rotation shaft 14 passes.

According to some embodiments, the impeller body 24 can be attached to the rear cap 21 to at least partly enclose the drive member 16.

According to some embodiments, the impeller body 24 comprises a pump body 26, located during use toward the drive member 16, which separates the impeller 12 from the drive member 16 and in which the through hole 25 is made.

According to possible solutions, the pump body 26 comprises a support portion 27, disposed in correspondence with the through hole 25.

According to some embodiments, the support portion 27 is provided with a positioning seating 23, facing toward the inside of the impeller body 24, in which a hydraulic seal device 36, 136 can be positioned, to prevent leakages of liquid from the impeller body 24 to the drive member 16.

According to some embodiments, the support portion 27 is provided with a housing seating 28, opposite the positioning seating 23, disposed in correspondence with the through hole 25, in which a support element 29 is positioned, configured to support the rotation shaft 14.

According to some embodiments, the support element 29 can be a bearing.

According to some embodiments, a Seeger elastic ring 40 can be provided, configured to clamp the support element 29 and keep it positioned in the housing seating 28.

The impeller body 24 can also comprise an introducer 30, positioned outside the impeller 12 and provided with an aperture 31 to allow to introduce the liquid into the impeller body 24.

According to some embodiments, the impeller body 24 is associated with a delivery pipe 32, through which the liquid pumped by the impeller 12 is made to transit.

According to one aspect of the present invention, in correspondence with the support portion 27, the pump body 26 is provided with discharge means 33, configured to allow to discharge possible leakages of liquid from the impeller body 24.

According to possible solutions, the discharge means 33 comprise at least one discharge groove 34.

According to possible embodiments, the at least one discharge groove 34 is made in the support portion 27 with the hollowed part facing toward the external surface 26a of the pump body 26 facing toward the drive member 16.

According to some embodiments, described for example with reference to fig. 2, three discharge grooves 34 can be provided, disposed angled with respect to an axis passing through the center of the through hole 25.

According to some embodiments, the discharge grooves 34 can be disposed radially with respect to the through hole 25.

The angles between the discharge grooves 34 can be defined as a function of the possible work positions of the pumping device 10. In this way, in each operating position of the electropump 10, at least one discharge groove 34 can be positioned facing downward, so as to exploit the force of gravity to channel the possible drops of liquid that have leaked through the through hole 25.

The discharge grooves 34 extend from an internal portion of the pump body 26, until they are substantially aligned externally with the housing seating 28 of the support element 29.

According to some embodiments, the discharge grooves 34 extend through the lateral walls of the housing seating 28.

According to possible solutions, the discharge grooves 34 can be made in such a way as to direct the possible drops of liquid onto the external surface 26a of the pump body 26.

The discharge grooves 34, for example, starting from their internal end facing toward the rotation shaft 14, can have a segment 34a inclined toward the back, that is, toward the introducer 30 and toward the external surface 26a, so as to discharge toward the outside of the pump body 26 the drops of liquid that have leaked in, preventing them from reaching the drive member 16.

According to variant embodiments, the pumping device 10 comprises a hydraulic seal device 36, 136, disposed between the impeller 12 and the support portion 27, configured to prevent the liquid from leaking through the through hole 25.

According to possible solutions described using fig. 3, the hydraulic seal device 36 is a mechanical seal device.

According to this solution, the hydraulic seal device 36 comprises a rotary portion 37, for example a rotary ring, keyed onto the rotation shaft 14, cooperating with a stationary portion 38, or a stationary ring, keyed onto a fixed part, for example on the pump body 26.

According to some embodiments, the rotary portion 37 and the stationary portion 38 are in contact with smoothed faces. The hydraulic seal between the impeller 12 and the support portion 27 is guaranteed by the pressure generated by the impeller 12 and by the centrifugal effect obtained with the rotation of the shaft 14, which cause a film to be created between the contact faces between the rotary portion 37 and the stationary portion 38, which film has a uniform thickness of the liquid subjected to sealing.

According to some embodiments, a gasket 39 can be provided, positioned between the impeller 12 and the rotary portion 37 to prevent leakages of liquids.

According to variant embodiments, a washer 41 can also be provided, disposed between the impeller 12 and the pump body 26 to facilitate the rotation of the impeller 12 with respect to the pump body 26.

According to possible variant embodiments described using fig. 4, the hydraulic seal device 136 is an oil seal interposed between the rotation shaft 14 and the pump body 26.

According to this solution, the oil seal device 136 can comprise a metal structure, configured to confer a certain resistance and stability thereto, covered by a compound which not only covers the metal structure but also functions as a seal, thanks to a lip seal 137.

According to some embodiments, the lip seal 137 can be assisted by a spring, to remain adherent to the rotation shaft 14. The lip seal 137 can also be single, double or can be associated with another lip seal with a dust-scraping function, so as to improve the working life of the lip seal 137.

According to possible embodiments, described using figs. 3 and 4, the pumping device 10 can comprise a seal body 42, positioned in the housing seating 28 between the pump body 26 and the second support element 29.

The seal body 42 can be configured to perform an anti-vibration function between the housing seating 28 and the second support element 29 of the rotation shaft 14.

It is clear that modifications and/or additions of parts may be made to the pumping device as described heretofore, without departing from the field and scope of the present invention.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of pumping device, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.