PUMPING ASSEMBLY

Technical Field

[01] The present invention relates to a pumping assembly. In particular, the invention relates to a pumping assembly predisposed to supply water to a domestic utility or to a domestic plumbing system..

Prior Art

[02] It is known the use of pumping assemblies predisposed to supply water or other liquids from a tank or from pressurized pipes to a predetermined use, for example domestic utilities and the like. Such pumping assemblies generally comprise an electric pumping element, for example a centrifugal pump; a regulating device, known as an inverter, adapted to control the flow generated by the pumping element; and a storage tank designed to absorb any flow irregularities, such as water hammers and the like.

[03] In the traditional technique, the components of the aforementioned pumping assemblies, often supplied by different manufacturers, are installed in a suitable place, assembling them on the spot. The installation of these pumping assemblies is relatively complicated and therefore requires a relatively long period of time, having to provide for the installation and the mutual connection of the individual components and the relative accessories. Moreover, the space they require is often quite large.

[04] Pumping assemblies have more recently been proposed in which the different components are already assembled, in compact form, inside a box-shaped casing. Pumping assemblies of this type are illustrated for example in patent applications EP 2 775 205 and EP 2 775 145.

[05] CN106249827 shows a pumping assembly used in a cooling system for CPU having a box-shaped casing.

[06] These pumping assemblies have a relatively small size and are able to simplify and make the installation quicker, as only the connection to the installation to be supplied need to be provided, essentially a suction and a water delivery pipe. In the known pumping assemblies, however, the fact that the connection elements of the pumping assembly are often not consistent with those of the plant is complained. During installation, it is therefore necessary to use additional connection elements, such as pipes and fittings, which complicate the installation itself and increase the required space.

[07] A specific problem that arises in the field in question is constituted by the fact that the supplying of individual utilities is often not regular and uniform as required. For example, utilities placed on different levels and supplied by a single centralized pumping assembly can be affected differently by variations in the water supply pressure from the water network. The need for pumping assemblies of reduced dimensions is thus felt, in particular of pumping assemblies which can be used at the single domestic utilities, so as to ensure a regular supply of water..

Disclosure

[08] The object of the present invention is to solve the aforementioned problems by devising a pumping assembly which ensures a regular supply of water to the individual utilities, such as domestic utilities.

[09] Within this task, a further object of the present invention is to provide a pumping assembly that can be connected easily and rapidly to the conventional pipes of the plumbing system.

[10] Another object of the present invention is to provide a pumping assembly that requires a reduced installation space.

[1 1] Another object of the invention is to provide a pumping assembly of simple constructional and functional conception, equipped with reliable operation, versatile in use, and having a relatively low cost.

[12] The aforementioned objects are achieved, according to the present invention, by the pumping assembly according to claim 1 .

[13] According the present invention, the pumping assembly comprises a box-shaped casing inside which are housed an electric pumping element, having a suction pipe and a delivery pipe, for connection to a water system; a regulating device adapted to control the flow generated by the pumping element; a storage tank.

[14] Preferably, the storage tank is an expansion vessel, adapted to absorb any water hammer and to reduce the number of pump starts due to hydraulic losses of the plumbing system.

[15] Preferably, the storage tank comprises a first part filled with water and a second part filled with air.

[16] Preferably, said first part and said second part are separated.

[17] Preferably, said first part and said second part have variable volume.

[18] Advantageously, the pumping assembly comprises a suction inlet and a delivery outlet with elbow shape adapted to be associated in a removable way with a side wall of said casing, at a relative seat defined by said suction pipe and by said delivery pipe.

[19] Preferably, the suction pipe and the delivery pipe are staggered, at respective portions adapted to be connected to the suction inlet and to the delivery outlet, so as not to be, when used, arranged on the same vertical plane.

[20] Preferably, the suction pipe and the delivery pipe are staggered, at the respective portions adapted to be connected to the suction inlet and to the delivery outlet, so as not to be, when used, arranged on the same horizontal plane.

[21] Advantageously, the suction inlet and the delivery outlet have the respective inlet and outlet axes lying on a plane parallel to the longitudinal axis of said electric pumping element in such a way as to be freely revolving on said plane parallel to the axis of the electric pumping element.

[22] Preferably, said electric pumping member is a multistage centrifugal electric pump.

[23] Preferably, said electric pumping element comprises an electric motor having a shaft arranged according to said longitudinal axis of the electric pumping element, in horizontal position on the median longitudinal plane of said casing.

[24] Preferably, said shaft of the electric motor is made accessible by means of an inspection plug provided on a rear wall of said casing .

[25] Preferably, said casing comprises a front wall on which are provided a drain plug of said pumping element; a vent plug of the same pumping element and an access plug to an inflation valve of said storage tank.

[26] Preferably, said electric pumping assembly comprises a hollow body of plastic material, inside which are housed said electric motor and a plurality of impeller units mounted in series on the shaft of the electric motor.

[27] Preferably, said electric motor has a steel liner that is made firmly integral with a stator pack.

[28] Preferably, between said hollow body of the pumping element and said liner of the electric motor is defined a cavity with annular section which is adapted to be crossed by the entire flow of water dispensed by the same pumping element.

[29] Preferably, said water dispensed by said pumping element comes out through a channel defined by said regulating device.

[30] Preferably, said channel is closed at the top by a filling plug arranged on the upper surface of said casing and having at the base a check valve adapted to seal close a seat defined by the inner surface of the same channel.

[31] Preferably, said check valve is subjected to an automatic opening device adapted to intervene when said filling plug is removed.

[32] Preferably, said automatic opening device comprises a lifting member which is kept aligned with said regulating device by guide means fixed to the regulating device itself and is pushed to elastic abutment of said filling plug.

[33] Preferably, said lifting member has a tubular shape and provides an axial guide for a stem of said check valve.

[34] Preferably, the centering between the said body of the pumping element and the said liner of the electric motor is provided by a shield adapted to close the pumping element from the rear.

[35] Preferably, said storage tank comprises a membrane seal constrained between a first shell and a second shell made mutually integral, so as to separate inside the storage tank itself a first part filled by the water and a second part filled by the air, said first part being in communication with said regulating device.

[36] Preferably, inside said second shell is arranged a diaphragm adapted to provide a regular supporting surface for said membrane in case of said storage tank being deflated.

[37] Conveniently, with said diaphragm is associated an ending part of a spacer slidable axially along said storage tank and adapted to operate a micro switch for detecting the deflation condition of the storage tank itself.

[38] Advantageously, the pumping assembly comprises an automatic closing valve device adapted to make said pumping member self-priming by means of the connection of the delivery to the suction.

[39] Preferably, the valve device comprises a shutter that is axially mobile inside a guide cap, between a first closing position in abutment on a sealing seat and a second opening position of the passage opening.

[40] Conveniently, said shutter is mushroom-shaped.

[41] Conveniently, said sealing seat is made of rubber-like material and is movable, so as to act as a shock-absorber to avoid a sudden impact of said shutter during closure.

[42] Advantageously, the said shutter is associated with a locking lever adapted to prevent the opening of said valve device in certain operating conditions, said locking lever being adapted to prevent axial sliding of the shutter itself.

[43] Preferably, said valve device is made accessible by means of the drain plug of said pumping element, so as not having to be extracted to perform the blocking or for other operations to modify the ordinary arrangement.

[44] Appropriately, said adjustment device is of the type known as a water passage inverter.

[45] Conveniently, the pumping assembly comprises a first pressure sensor adapted to provide a counter-reaction signal for controlling said inverter, said first pressure sensor being arranged in a housing formed in said first shell of the storage tank, which is permanently in pressure connection with the delivery of said pumping element.

[46] Preferably, the pumping assembly comprises a second pressure sensor, arranged in a housing formed in said second shell of the storage tank, so as to detect under normal operating conditions the same pressure of said first pressure sensor, said second pressure sensor enebling the detection of the deflation condition of said storage tank.

[47] Conveniently, the pumping assembly has an integrated device for detecting and controlling the depression on the suction of said pumping element.

[48] Preferably, said integrated depression detection and control device comprises a vacuum sensor installed on the suction body and directly connected to an interface card, in which the software of said interface card controls the degree of vacuum in suction and stops said pumping element if it rises above the permitted values.

Description of drawings [49] The details of the invention will become more evident from the detailed description of a preferred embodiment of the pumping assembly according to the invention, illustrated by way of example in the accompanying drawings, in which:

Figure 1 shows a side view of the pumping assembly;

Figure 2 shows a front view thereof;

Figure 3 shows a longitudinal section view of the pumping assembly according to the trace plane Ill-Ill in Figure 2;

Figures 4 and 5 show a cross-sectional view, respectively, according to the plane of trace IV-IV and V-V in Figure 1 ;

Figures 6 and 7 show respectively a sectional view of a detail of the pumping assembly in two different operating positions.

Best mode

[50] With particular reference to these figures, the pumping assembly object of the invention has been indicated as a whole with 1 .

[51] The pumping assembly 1 comprises a box-shaped casing 2 inside which the operating members of the pumping assembly are housed, in particular an electric pumping element 3, preferably a multi-stage centrifugal electric pump; a regulating device 4 of the type known as a water passage inverter, adapted to control the flow generated by said pumping member 3; and a storage tank 5 having the function of damping any water hammer and reducing the number of starts of the pumping element 3 against hydraulic losses of the downstream system of the same pumping assembly.

[52] The casing 2 comprises substantially a first side wall 20, to which a suction inlet 10 and a delivery outlet 1 1 are associated in a removable manner, as better specified below; a second side wall 21 opposed to the previous one, on which a general switch 22 is arranged; a front wall 23 and a rear wall 24.

[53] On the front wall 23 are provided a drain plug 25 of the pumping element 3, a vent plug 26 of the same pumping element 3 and a plug 27 for accessing the inflation valve of the storage tank 5, the function of which is described below. On the upper surface of the casing 2 there is also a filling plug 28.

[54] The suction inlet 10 and the delivery outlet 1 1 are connected, in use, respectively to a suction pipe 12 and to a water delivery pipe 13 connected to the electric pumping element 3.

[55] The suction pipe 12 and the delivery pipe 13 are staggered, at respective portions adapted to be connected to the suction inlet 10 and to the delivery outlet 1 1 , so as not to be, when used, arranged on the same vertical plane or on the same horizontal plane (see Fig. 1 ).

[56] According to the present invention, the suction inlet 10 and the delivery outlet 1 1 are elbow-shaped and have the respective outlet axes lying on a plane parallel to the longitudinal axis of said electric pumping element 3 in such a way as to be freely revolving on said plane parallel to the axis of the electric pumping element 3 (see in particular Figures 4 and 5).

[57] More specifically, the terminal part 14 of the suction inlet 10 and of the delivery outlet 1 1 , for example provided with threading, can be connected in a traditional manner to the suction pipe and to the delivery pipe of the water system, not shown.

[58] The suction inlet 10 and the delivery outlet 1 1 engage quickly in a relative seat defined by the suction pipe 12 and by the delivery pipe 13 at the side wall 20 of the casing 2 and are retained by the insertion of a locking fork 15. Suitable annular seals 16 ensure the necessary seal in the seat.

[59] The electric pumping assembly 3 comprises a hollow body 30 of plastic material, inside which are housed an electric motor 31 , of the water-cooled type, and a plurality of impeller units 32 mounted in series on the shaft 33 of said electric motor 31 . The shaft 33 of the electric motor 31 is arranged according to the longitudinal axis of the electric pumping element 3, in horizontal position on the median longitudinal plane of the casing 2. The shaft 33 of the electric motor 31 is made accessible by means of a plug 29 provided on a rear wall 24 of the casing 2, so as to enable its inspection or maintenance.

[60] The electric motor 31 provides a steel liner 34 that is made firmly integral with a stator pack 35. Between the body 30 of the pumping element 3 and the liner 34 of the electric motor 31 is defined a cavity 36 with annular section which is crossed by the entire flow rate of water dispensed by the same pumping element 3. The water dispensed by the pumping element flows out through a channel 41 defined by the body 40 of the inverter 4. The channel 41 is closed at the top by a filling plug 28 having at the base a check valve 42 that seal closes, by means of a sealing ring 43, a seat defined by the inner surface of the same channel 41. The valve 42 is held in position by an elastic member, for example a helical spring.

[61] According to a prerogative of the pumping assembly in question, the valve 42 is subjected to an automatic opening device adapted to intervene when the filling plug 28 is removed. This device comprises a lifting member 44 which is kept aligned with the body 40 of the inverter 4 by a guide 45 fixed to the same body 40 and is pushed in abutment of the filling plug 28, in use, by a further elastic element, for example a helical spring. The lifting member 44 has a tubular shape and provides an axial guide for the stem of the valve 42.

[62] When the filling plug 28 is in the closed position, the lifting member 44 is kept in the lowered position and acts axially on the stem of the valve 42, which seal closes, by means of the sealing ring 43, the seat defined by the internal surface of the channel 41. The flow generated by the pumping element 3 can lift the valve 42, whose stem slides inside the tubular lifting member 44, in contrast with the action of the elastic member which brings the valve 42 back to its closed position as soon as the flow stops.

[63] When the filling plug 28 is removed, the lifting member 44 is pushed into the raised position by the action of the further elastic member. The lifting member 44 hooks a plurality of teeth present on the stem of the valve 42 and moves the valve 42 upwards, enabling the passage of the filling water.

[64] The vent plug 26 positioned at the front enables the complete filling of the pumping element 3 and the evacuation of the air, without any overflowing of the filling plug 28.

[65] The centering between the body 30 of the pumping element 3 and the liner 34 of the electric motor 31 is provided by a shield 37 that closes the pumping element 3 from the rear. The rear shield 37 is preferably made of aluminum. An annular seal 38 ensures the necessary seal between the body 30 and the liner 34.

[66] A series of support feet 6 are also fixed by screwing to the body 30 of the pumping element 3, for example a number of four, predisposed to support the pumping assembly in use in the installation position. Conveniently, the support feet 6 are of antivibration type, for example of rubber or the like, and are individually adjustable. It is possible to provide that one or more of said support feet 6 can be fixed to the floor.

[67] The storage tank 5 is arranged in the upper part of the pumping assembly, above the pumping element 3. Preferably the storage tank 5 is of the so-called membrane type, in which a membrane 50 is seal constrained between a first shell 51 and a second shell 52 made mutually integral, so as to separate inside a storage tank 5 a first part 53 filled by the water and a second part 54 filled by the air (Fig. 3). The first part 53 is in communication with a tube 48 shaped by the body 40 of the inverter 4 transversely to the channel 41 . In particular, the first shell 51 forms a sleeve 56 which engages on the tube 48. The seal between this sleeve 56 and the tube 48 is secured by an annular seal 49.

[68] In a known manner, if the storage tank 5 has lost the correct inflation on the air side, the water pressure pushes the membrane 50 to adhere to the inner wall of the second shell 52.

[69] Conveniently, according to the present invention, a diaphragm 55 is arranged inside the second shell 52, adapted to provide the membrane 50 with a regular support surface in the event that the tank is deflated. In practice, when the storage tank 5 is regularly inflated, the membrane 50 moves on the inner wall of the first shell 51 when the pressure of the water system is lower than the inflation pressure of the air region 54 and on the contrary towards the diaphragm 55 when the pressure of the water system is higher than the inflation pressure.

[70] Under normal operating conditions, the membrane 50 never comes into contact with the diaphragm 55. If however, for any reason, the storage tank 5 is completely deflated, the membrane 50 lies down on the diaphragm 55, avoiding possible damage.

[71] The inflation of the storage tank 5 is achieved by means of a conventional valve 57 arranged at the front wall 23 of the casing 2. The inflation valve 57 is covered by the access plug 27.

[72] Suitably, an end of a spacer 58 consisting of a stem axially slidable along a seat formed in the shell 52 of the storage tank 5 is associated with the diaphragm 55. At the opposite end, the spacer 58 is adapted to operate a microswitch 59 for detecting the deflation condition of the storage tank 5 which enables a suitable alarm signal to be activated.

[73] The pumping element 3 is associated with a automatic-closing valve device 7 for making the pumping element 3 self-priming by connecting the delivery to the suction. In a known manner, said valve device 7 remains open in the self-priming phases until the pressure difference between the delivery and the suction reaches a predetermined value and vice versa is closed during normal operation.

[74] More specifically, the valve device 7 comprises a mushroom-shaped shutter 70 which is movable axially within a guide cap 71 , between a first closing position in abutment with a sealing seat 73 (Fig. 6) and a second opening position of the passage opening (Fig. 7). The sealing seat is made of rubber-like material. Conveniently, the sealing seat 73 is movable, so as to act as a shock-absorber to avoid a sudden impact of the shutter 70 during closure. This permits to eliminate the noise of the valve device 7.

[75] With the shutter 70 is associated a locking lever 74 which is adapted to prevent the valve device 7 from opening in certain operating conditions, for example when the pumping element 3 operates under a head or sucks from a pipeline under pressure so that it is guaranteed the filling at the first start. In practice, the angular rotation of the locking lever 74, in the position shown in Fig. 6, prevents the axial sliding of the shutter 70 which is kept stably in this way in the closed position in abutment with the sealing seat 73.

[76] It should be noted that the valve device 7 is made accessible through the drain plug 25 of the pumping element 3 and must not be removed to perform the blocking or for other operations of modification of the normal attitude.

[77] Conveniently, the pumping assembly has a pressure sensor predisposed to provide the feedback signal for controlling the inverter 4. This pressure sensor is arranged in a suitable housing formed in the first shell 51 of the storage tank 5 which is permanently in pressure connection with the delivery of the pumping element 3. A second pressure sensor arranged in turn in a suitable housing formed in the second shell 52 of the storage tank 5 which, under normal operating conditions, detects the same pressure as the first sensor, permits to detect the deflation condition of the storage tank 5 and report it using a special software.

[78] The pumping assembly is also conveniently equipped with an integrated vacuum sensing and control device on the suction of the pumping element 3 which comprises a vacuum sensor installed on the suction body and directly connected to an interface card. The software of said interface card controls the degree of vacuum in suction and stops the pumping element 3 if it rises above the permitted values.

[79] The operation of the pumping assembly is easily understandable from the above description.

[80] Upon installation, the suction inlet 10 and the delivery outlet 1 1 can be easily connected, through the threaded terminal part 14, to the traditional fittings associated to the suction pipe and to the delivery pipe of the water system. The suction inlet 10 and the delivery outlet 1 1 are then rapidly engaged in the relative seat defined by the suction pipe 12 and by the delivery pipe 13 of the pumping element 3, on the side wall 20 of the casing 2. The suction inlet 10 and the delivery outlet 1 1 are retained by the insertion of a relative locking fork 15.

[81] According to a prerogative of the invention, the suction inlet 10 and the delivery outlet 1 1 are elbow-shaped and are freely rotatable on a vertical plane parallel to the axis of the pumping element 3. This permits to orient the suction inlet 10 and the delivery outlet 1 1 in the most appropriate position for connection to the suction pipe and to the delivery pipe of the water system, according to the arrangement of the pipes themselves. It should be noted that the angular rotation of the suction inlet 10 and of the delivery outlet 1 1 is made possible even when the aforementioned pipes are already connected thereto through the threaded terminal part 14.

[82] The pumping assembly according to the invention therefore achieves the purpose of ensuring a regular supply of water to the individual users, for example domestic users.

[83] The aforementioned pumping assembly is also quick and easy to use even in the management and carrying out of any control or maintenance operations. In particular, the discharge and the vent of the pumping element 3, the access to the inflation valve of the storage tank 5 and the filling of the channel 41 of the inverter 4 can be easily performed by unscrewing the relative plugs on the front part and on the upper surface of the casing 2.

[84] Another advantage offered by the pumping assembly is the fact that it enables the connection of wired input and output signals for remote alarm control or signaling.

[85] The pumping assembly described as an example is susceptible of numerous modifications and variations depending on the different needs.

[86] In the practical embodiment of the invention, the used materials, as well as the shape and the dimensions, may be any according to requirements.

[87] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of 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.