pump group

Abstract

The present invention is a pump group (1) fluidically connectable to a cooling system of an operating group of a vehicle, for example an internal combustion engine, an electric motor or a battery pack. The pump group (1) comprises an impeller (2) and a shaft (3) on which the impeller (2) is integrally mounted. The pump group (1) comprises an electric motor (4) comprising a rotor (41) integrally mounted on the shaft (3) and a stator (42). Furthermore, the pump group (1) comprises an electronic command board (5) connected to the electric motor (4). Furthermore, the pump group (1) comprises a pump body (6) comprising a first casing (61) in which the impeller (2) is housed, a second casing (62) comprising an intermediate tubular wall (625) positioned between the rotor (41) and the stator (42) so as to define, in a motor chamber (620), a rotor chamber (621) and a stator chamber (622) which are mutually separated and fluidically sealed, a third casing (63) in which the electronic command board (5) is housed in a command chamber (630). The pump group (1) of the present invention contains a quantity of oil in the stator chamber (622) and in the command chamber (630) which cools the stator (42) and the electronic command board (5) by convection, wherein the command chamber (630) and the stator chamber (622) are separated by a second separation wall (623) comprising at least one connection opening (623') which fluidically connects the command chamber and the stator chamber.

Description

[0001] The present invention relates to a pump group for a cooling system of a vehicle.

[0002] In the course of the description, the term "vehicle" refers to any mobile means comprising an internal combustion engine and hybrid vehicles, without any limitation related to the type or size, i.e. motor cars or articulated vehicles.

[0003] In other words, the present invention relates to the automotive sector and, in detail, to the thermal management system of a vehicle.

[0004] In particular, the cooling system is dedicated to cooling the "operational group" of the vehicle.

[0005] In particular, in the present description, the "operational group" refers to the components or groups of components dedicated to performing specific operations necessary for the movement of the vehicle. In a preferred embodiment, the "operational group" comprises an engine group, for example of the heat-absorbing type or of the electric type.

[0006] In other embodiments, the "operational group" comprises other components of the vehicle, i.e. both mechanical type components (for example a transmission assembly) and electrical type components (for example a "battery assembly" comprised in the vehicle).

[0007] In the prior art, it is known that the pump groups for the cooling system of the operational group differ from each other in a plurality of embodiments in terms of size and type of actuator.

[0008] In particular, the pump group of the present invention is one in which there is an electric type driver. In other words, the pump group object of the present invention comprises at least one electric motor which controls the rotational movement of the impeller comprised therein, thus controlling the movement of the cooling liquid flowing in the cooling system which can be fluidically connected to the pump group. A plurality of technical solutions are known of pump groups comprising an electric driver, in which pump groups of this type there is the major problem, which cannot be avoided, of the need to effectively cool the electric motor of the pump group and the components related thereto.

[0009] In particular, a plurality of embodiments of the pump group are known in which the cooling liquid present in the chamber which houses the impeller is also used to cool the electric motor and the components related thereto. Even more in particular, in the prior art, it is known that there is attention to the cooling of the rotor comprised therein using the cooling liquid.

[0010] Furthermore, a plurality of embodiments of the pump group are known in which the problems associated with the cooling of the stator are also solved.

[0011] In some embodiments, the pump group has been designed to favor the cooling of the stator, making it thermally divergent towards the external environment.

[0012] However, in other embodiments, a certain amount of oil is provided in the stator chamber with the purpose of cooling the stator chamber containing the oil by convection. An example showing such a pump group solution is shown for example in document WO 2020 / 07562 of the present applicant.

[0013] On the other hand, these embodiments effectively cool the rotor and / or stator, but fail to effectively cool the rest of the pump assembly.

[0014] Therefore, an object of the present invention is to provide a pump unit for a cooling system of a vehicle operating unit, which effectively cools the entire electronic control component, thereby eliminating the problems described above.

[0015] This object is achieved by a pump assembly according to claim 1. The dependent claims relate to preferred embodiment variants having further advantageous aspects.

[0016] The object of the invention is described in detail below with the aid of the accompanying drawings, in which:

[0017] - Figure 1 shows a longitudinal section through a pump assembly according to the invention in a vertical operating position according to a possible embodiment;

[0018] - Figure 2 shows a longitudinal section through a pump assembly according to the invention in a horizontal operating position according to a possible embodiment;

[0019] - Figure 3 A longitudinal section through a pump assembly according to the invention is shown in an oblique position according to a possible embodiment.

[0020] In the above list, reference numeral 1 generally indicates a pump group for a cooling system of a vehicle operating group, preferably a pump group for cooling an engine group, for example of the internal combustion type.

[0021] The pump assembly 1 according to the invention extends in length mainly relative to the axis XX.

[0022] The pump unit 1 object of the invention comprises an impeller 2 rotatable relative to said axis XX. In other words, said impeller 2 has a centre of rotation situated on said axis XX.

[0023] Preferably, the impeller 2 is a radial type impeller specifically shaped to perform a suction action on the coolant, preferably in the axial direction, and a thrust action, preferably in the radial direction. In particular, the "coolant" is a water-based liquid, for example a solution comprising water and ethylene glycol, which circulates in the cooling system of the vehicle to which the pump assembly 1 object of the present invention can be fluidically connected.

[0024] Furthermore, according to the invention, the pump unit 1 comprises a shaft 3 extending in length along the axis XX. Preferably, said shaft 3 comprises a rotating end 32 on which the impeller 2 is integrally mounted.

[0025] According to the invention, the pump unit 1 comprises an electric motor 4 adapted to drive a shaft 3 in rotation.

[0026] The electric motor 4 comprises a rotor 41 and a stator 42. According to a preferred embodiment, the rotor 41 and the stator 42 are arranged concentrically with respect to the axis XX.

[0027] According to the present invention, the rotor 41 is integrally mounted (e.g., keyed) on the shaft 3: the rotation of the shaft 3 and, consequently, the rotation of the impeller 2 corresponds to the electrically controlled rotation of the rotor 41. The stator 42 axially and circumferentially surrounds the rotor 41. Specifically, the stator 42 includes a plurality of stator coils forming the stator.

[0028] According to the invention, the pump unit 1 comprises an electronic command board 5 operatively connected to the motor shaft 3 and adapted to command the rotation of this shaft about the axis XX. In other words, the electronic board 5 controls the operation of the electric motor 4 and therefore the rotation of the shaft 3 and, consequently, of the impeller 2.

[0029] According to the invention, the pump unit 1 comprises a pump body 6 extending parallel to the axis XX and mainly around the same. The pump body 6 is adapted to contain the various operating components of the pump unit 1 and to be fluidically connectable to the vehicle cooling system.

[0030] According to the invention, the pump body 6 comprises, along the axis XX:

[0031] - a first housing 61 in which the impeller 2 is housed in an impeller chamber 610;

[0032] A second housing 62 in which the electric motor 4 is housed in a motor chamber 620 ; specifically, the motor chamber 620 houses the rotor 41 and the stator 42 .

[0033] A third housing 63 in which the command board 5 is housed in a command chamber 630 .

[0034] According to the invention, the second housing 62 comprises an intermediate tubular wall 625 extending parallel to the axis XX and positioned between the rotor 41 and the stator 42 .

[0035] The intermediate tubular wall 625 divides the rotor chamber 621 and the stator chamber 622 in the second housing 62. In other words, the motor chamber 620 is divided into the rotor chamber 621 and the stator chamber 622. Preferably, the rotor chamber 621 and the stator chamber 622 are fluidically tightly separated from each other.

[0036] According to a preferred embodiment, the first housing 61 and in particular the impeller chamber 610 included therein is fluidically connected to a pipe of a cooling system in which a coolant flows.

[0037] According to a preferred embodiment, the first housing 61 and the second housing 62 are separated by a first separation wall 624. The first separation wall 624 axially delimits and fluid-tightly seals the motor chamber 620.

[0038] Preferably, the first separation wall 624 is included in the first housing 61 .

[0039] In an alternative embodiment, the first separating wall 624 is included in the second housing 62 .

[0040] In another embodiment, a portion of the first separating wall 624 is included in the first housing 61 and another portion is included in the second housing 62 .

[0041] Preferably, the first separating wall 624 is traversed by the shaft 3 and supports the shaft.

[0042] According to a preferred embodiment, the first separating wall 624 comprises at least one cooling hole 624 ′ suitable for placing the rotor chamber 621 in fluid communication with the impeller chamber 610 so as to allow a cooling liquid to flow also in said impeller chamber 610 .

[0043] According to a preferred embodiment, the intermediate tubular wall 625 extends and includes a first end 625 ′ proximate the first housing 61 and a second end 625 ″ proximate the second housing 62 , which preferably fluid-tightly engages the first separating wall 624 and which fluid-tightly engages the second separating wall 623 .

[0044] According to the invention, the command chamber 630 and the stator chamber 622 are separated by a second separating wall 623. Said second separating wall 623, together with the first separating wall 624, axially delimits and seals the motor chamber 620 in a fluid-tight manner.

[0045] In the first preferred embodiment, the second separation wall 623 is included in the second housing 62 .

[0046] In the second preferred embodiment, the second separation wall 623 is included in the first housing 61 .

[0047] In another embodiment, a portion of the second separating wall 623 is included in the second housing 62 and another portion is included in the third housing 63 .

[0048] According to a preferred embodiment, the third housing 63 includes a closing cover 635 adapted to tightly seal the command chamber 630 accommodating the electronic command board 5 .

[0049] In a preferred embodiment, the second housing 62 comprises an annular side wall 627 extending parallel to the axis XX. Furthermore, said side wall 627 radially delimits the motor chamber 620 , preferably the stator chamber 622 .

[0050] Preferably, the side wall 627 tightly engages the first separating wall 624 and the second separating wall 623 .

[0051] According to the present invention, the stator chamber 622 and the command chamber 630 contain a certain amount of oil. Specifically, the amount of oil is such that the stator chamber 622 and the command chamber 630 are at least partially filled, thereby cooling the stator 42 and the electronic command board 5 by convection. In other words, the oil at least partially fills the free space in the stator chamber 622 (i.e., the space not occupied by the stator 42) and the free space in the command chamber 630 (i.e., the space not occupied by the electronic command board 5).

[0052] According to the present invention, the oil and the coolant circulate in different parts of the pump unit without mixing.

[0053] Preferably, the oil is dielectric.

[0054] Furthermore, according to the invention, the second separating wall 623 comprises at least one connecting opening 623 ′ which fluidically connects the command chamber 630 and the stator chamber 622 .

[0055] In other words, the at least one connecting opening 623 ′ is passable in both directions by the oil present in the command chamber 630 and in the stator chamber 622 .

[0056] According to a preferred embodiment, the second separating wall 623 includes at least one connecting opening 623' at a position away from the axis XX. In other words, the at least one connecting opening 623' is at a position away from the tubular wall 625. In other words, the at least one connecting opening 623' is at a position close to the side wall 627 of the second housing 62.

[0057] According to a preferred embodiment, the second separating wall 623 comprises a plurality of connecting openings 623 ′ arranged at equal angular intervals relative to the axis XX.

[0058] In fact, preferably, the second separating wall 623 comprises at least three connecting openings 623' arranged at equal angular intervals. In this way, relative to the imaginary plane in which the axis XX lies, at least one opening is located on one side.

[0059] In an embodiment variant, the second separating wall 623 comprises a plurality of connecting openings 623 ′ comprising a first group of openings remote from the axis XX and a second group of openings close to the axis XX.

[0060] According to a preferred embodiment, the second separating wall 623 defines a pair of distinct but concentric circumferences relative to the axis XX, the second separating wall 623 comprising, for example, three angularly equidistant connecting openings 623 ′ on each of the two circumferences.

[0061] According to a preferred embodiment, the electronic command board 5 is housed in the command chamber 630 in a region close to the second separating wall 624 .

[0062] In a preferred embodiment, the electronic instruction board 5 is fixed (for example, glued or mechanically fixed) to the second separating wall 623. In other words, the electronic instruction board 5 is preferably in contact with the second separating wall 623.

[0063] Preferably, such positioning of the electronic command board 5 involves a higher heat exchange with the wall, thus contributing to cooling the electronic command board 5 .

[0064] According to a preferred embodiment, the electronic command board 5 includes at least one connecting pipe 55 axially passing through the electronic command board 5 .

[0065] According to a preferred embodiment, oil flows in the at least one connecting pipe 55 .

[0066] According to a preferred embodiment, the oil flowing between the command chamber 630 and the stator chamber 622 flows in the connecting pipe 55 without being restricted in direction.

[0067] According to a preferred embodiment, the electronic command board 5 includes a plurality of connecting pipes 55 .

[0068] In a preferred embodiment, the number of connecting tubes 55 is equal to the number of connecting openings 623 ′. For example, in one embodiment, the number of connecting openings 623 ′ is three, and the number of connecting tubes 55 is three.

[0069] Preferably, the connecting pipe 55 is positioned to face the connecting opening 623 ′.

[0070] According to a preferred embodiment, the shaft 3 comprises an axial hole 300 extending mainly along the axis XX.

[0071] Preferably, the coolant flows inside the axial hole 300. Preferably, the axial hole 300 passes along the shaft 3.

[0072] According to a preferred embodiment variant, the third housing 63 and the second housing 62 delimit an auxiliary cooling chamber 631 fluidically connected to the rotor chamber 621 , so that the cooling liquid also fluidically reaches said auxiliary cooling chamber 631 .

[0073] According to a preferred embodiment, said auxiliary cooling chamber 631 is reached by a cooling liquid flowing through an axial hole 300 included in the shaft 3 .

[0074] In other words, the axial hole 300 connects the impeller chamber 610 and the auxiliary cooling chamber 631 in a fluid connection.

[0075] According to the invention, the amount of oil and the position of the connection opening 623 and of any connection pipe 55 are such as to facilitate the exchange of heat present in the stator chamber 622 and the command chamber 630 by convection towards the “hydraulic part” of the pump group 1. In other words, the amount of oil and the position of the connection opening 623 and of any connection pipe 55 are such as to fill the stator chamber 622 and the command chamber 630 in such a way as to always wet the surface of at least one wall defining the chamber in which the cooling liquid of the system flows (for example the impeller chamber 610 or the rotor chamber 621 or the auxiliary cooling chamber 631).

[0076] According to a preferred embodiment, the amount of oil and the position of the connection opening 623 and of any connecting pipe 55 are such that, when the pump group 1 is positioned in the vehicle in any operating position, they facilitate heat exchange by convection of the heat present in the stator chamber 622 and the command chamber 630 towards the "hydraulic part" of the pump group 1.

[0077] In other words, according to a preferred embodiment, the pump assembly 1 can be positioned in a vehicle in a vertical position, a horizontal position or an inclined position and always have the same cooling mode.

[0078] According to a preferred embodiment, oil fills the stator chamber 622 so that the entire free surface of the coil is wetted. In this embodiment, the entire stator 42 is in an oil bath.

[0079] According to a preferred embodiment, the oil fills the entire command chamber 630 so that the entire surface of the electronic command board 5 is wetted. In other words, the electronic command board 5 is in an oil pool.

[0080] According to the invention, the presence of oil in the stator chamber 622 and the command chamber 630 ensures that the components contained therein are cooled by natural convection during static steps of the vehicle and by forced convection during moving steps of the vehicle.

[0081] According to a preferred embodiment, the amount of oil filling a portion of the stator chamber 622 and a portion of the command chamber 630 defines a free surface so that the oil can move freely when the pump group 1 is subjected to vibrations (for example due to the movement of a vehicle), thereby facilitating forced convection cooling.

[0082] Innovatively, the pump unit fully achieves the intended purpose by overcoming typical problems of the prior art.

[0083] In fact, advantageously, the pump unit comprises convection oil and specific fluid channels suitable for allowing the oil to wet the components to be heated as well as the components to be cooled by the flow of coolant, thus contributing to the convection cooling of said components.

[0084] Advantageously, the heat generated by the electronic components is efficiently conducted and transferred to the cooling liquid.

[0085] Advantageously, the at least one connecting opening allows an enhanced movement of oil between the plurality of chambers, thereby improving the heat exchange of the entire pump assembly.

[0086] Advantageously, the positioning of the connecting openings allows oil to flow between the plurality of chambers when the pump unit is in any orientation.Advantageously, the pump unit may be positioned at any position within the vehicle.

[0087] Advantageously, in the pump group object of the present invention, the "insulation" effect is usually greatly reduced due to the presence of a space with air therein. In fact, advantageously, the possibility of air becoming an insulating screen for the heat generated by the stator and / or command plate is eliminated.

[0088] Advantageously, the oil allows the pump group to operate at a uniform temperature.Advantageously, the presence of oil in the stator chamber and the command chamber allows a uniform temperature.

[0089] Advantageously, the pump set object of the invention has a greater power compared to known pump sets of the same size. Advantageously, the pump set object of the invention has more compact dimensions compared to known pump sets of the same size.

[0090] It is obvious that a person skilled in the art may modify the invention described above to meet contingent needs, all of which fall within the scope of protection defined in the appended claims.

Claims

1. A pump assembly (1) for a cooling system of an operating group of a vehicle, said pump assembly extending relative to an axis (XX) and comprising: i) an impeller (2) rotatable about said axis (XX); ii) a shaft (3) extending along the axis (XX) and on which the impeller (2) is integrally mounted; iii) an electric motor (4), comprising: a rotor (41) integrally mounted on the shaft (3); and a stator (42) axially and circumferentially surrounding the rotor (41); iv) an electronic command board (5) operatively connected to the electric motor (4); v) a pump body (6) comprising, along said axis (XX): - a first housing (61) in which the impeller (2) is housed in an impeller chamber (610); - a second housing (62) in which the electric motor (4) is housed in a motor chamber (620), wherein the first housing (61) and the second housing (62) are separated by a first separating wall (624), wherein the second housing (62) comprises an intermediate tubular wall (625) extending parallel to the axis (XX) and positioned between the rotor (41) and the stator (42), the intermediate tubular wall (625) comprising a first end (625') fluid-tightly engaging the first separating wall (624) and a second end (625") fluid-tightly engaging the second separating wall (623) so as to define a rotor chamber (621) and a stator chamber (622) fluid-tightly separated from each other in the motor chamber (620), - a third housing (63) in which the electronic command board (5) is housed in a command chamber (630); wherein the command chamber (630) and the stator chamber (622) are separated by the second separation wall (623), the second separation wall comprising at least one connecting opening (623'), the at least one connecting opening fluidically connecting the command chamber (630) and the stator chamber (622); wherein the stator chamber (622) and the command chamber (630) contain a quantity of oil that at least partially fills the command chamber (630) and at least partially fills the stator chamber (622) such that the stator (42) and the electronic command board (5) are cooled by convection; The second separation wall (623) includes a plurality of connection openings (623') arranged at equal angular intervals, and the plurality of connection openings can be passed through by the oil present in the command chamber (630) and the stator chamber (622) in two directions.

2. The pump assembly (1) according to claim 1, wherein The oil is of dielectric type.

3. Pump assembly (1) according to any one of the preceding claims, wherein The electronic instruction board (5) is housed in the instruction chamber (630) in an area close to the second separating wall (623).

4. Pump assembly (1) according to any one of the preceding claims, wherein Said second separating wall (623) comprises at least one connecting opening (623') at a position remote from said axis (XX).

5. Pump assembly (1) according to any one of the preceding claims, wherein The second separating wall (623) comprises a first set of connecting openings positioned away from the axis (XX) and a second set of connecting openings positioned close to the axis (XX).

6. Pump assembly (1) according to any one of the preceding claims, wherein The electronic command board (5) includes at least one connection pipe (55) passing through the electronic command board (5), wherein oil flows in the connection pipe (55) to cool the electronic command board (5).

7. Pump assembly (1) according to any one of the preceding claims, wherein The first housing (61) and the second housing (62) are separated by a first separation wall (624), wherein the oil fills the stator chamber (622) to at least partially wet the first separation wall (624).

8. Pump assembly (1) according to any one of the preceding claims, wherein The intermediate tubular wall (625) extends and includes a first end (625') proximate the first housing (61) and a second end (625") proximate the third housing (63), wherein the oil fills the stator chamber (622) to at least partially wet the intermediate tubular wall (625).

9. Pump assembly (1) according to any one of the preceding claims, wherein The third housing (63) and the second housing (62) define an auxiliary cooling chamber (631) fluidically connected to the rotor chamber (621), so that the cooling liquid also reaches the auxiliary cooling chamber (631) in a fluid manner.

10. Pump assembly (1) according to claim 9, wherein The oil fills the command chamber (630) to at least partially wet the second separating wall (623) in a region close to the auxiliary cooling chamber (631).

11. Pump assembly (1) according to any one of the preceding claims, wherein The third housing (63) comprises a closure cover (635) which seals the command chamber (630) in a fluid-tight manner.

12. Pump assembly (1) according to any one of the preceding claims, wherein The rotor chamber (621) is fluidly connected to the impeller chamber (610) so that cooling liquid flows in the rotor chamber (621).

Images