EP3615811B1

EP3615811B1 - Pump group with fixing element

Info

Publication number: EP3615811B1
Application number: EP18723060.2A
Authority: EP
Inventors: Daniele BELCUORE
Original assignee: Industrie Saleri Italo SpA
Current assignee: Industrie Saleri Italo SpA
Priority date: 2017-04-27
Filing date: 2018-04-16
Publication date: 2022-03-23
Anticipated expiration: 2038-04-16
Also published as: EP3615811A1; IT201700045437A1; CN110621883B; CN110621883A; WO2018197989A1

Description

The present invention concerns a pump group for cooling systems, in particular for vehicles. Specifically, the pump group that is object of the present invention is used in a vehicle cooling system for cooling its engine group, for example one of an internal combustion type, or for cooling other components of the vehicle, such as, for example, the gearbox or transmission group or the turbo group or the exhaust gas recirculation group.
More specifically, the pump group that is object of the present invention is of the electric drive type, comprising therein an electrically controlled electric motor, which drives the impeller in rotation as needed, circulating the coolant in the cooling circuit.
In the prior art there are already known pump groups of such type.
Such pump groups, however, present the problem of containing both components that must be in direct contact with the coolant as well as electrical components that must be separated from the coolant.
For this reason, in the state-of-the-art solutions, embodiments of pump groups are known composed of a large number of components which have particularly complex shapes and geometries. It is therefore intuitive that the greater the number of said components, the more complex are the shapes and geometries of the pump groups and, in particular, the shapes and geometries of the components themselves comprised therein. Similarly, the greater the number of such components, the more difficult it is to assemble them and the higher the costs for production and assembly. Examples of such pump groups are disclosed in documents EP3001037A1 , EP2927491A1 and US2014/205480.
The present invention is placed in the preceding context, having the object of creating a pump group for a vehicle cooling system that solves the aforementioned technical problems afflicting state-of-the-art solutions; in other words, the object of the present invention is to supply to the market a pump group that has a simple structure and geometry, is easy to design and produce, and provides simple assembly and disassembly procedures.
Such object is achieved by a pump group made according to claim 1. The claims dependent on this claim show preferred embodiments.
The object of the present invention will now be described in detail, with the aid of the accompanying figures, provided by way of illustrative and non-limiting example, wherein:

figure 1 shows a perspective view of a pump group according to the present invention;
figure 2 represents a longitudinal sectional view in perspective of the pump group shown in figure 1;
figure 3 illustrates a longitudinal sectional view in perspective of the pump group shown in figure 1;
figure 4 represents a cross-sectional view of the pump group shown in figure 1;
figure 5 illustrates a perspective view in separate parts of an embodiment of the pump structure comprised in the pump group shown in the above figures;
figure 6 shows a longitudinal sectional view of the pump structure as shown in figure 5.

With reference to the accompanying figures, a pump group for a cooling circuit is indicated in its entirety at reference number 1. Preferably, said pump group 1 is connectable fluidically with the cooling circuit of a vehicle to command the circulation of the coolant inside the ducts thereof.
The pump group 1, object of the present invention, extends in height along and around a main axis X-X.
The pump group 1 comprises an impeller 2, rotating in rotation around the axis X-X. Preferably, said impeller 2 is of the radial type, i.e. it receives the coolant in a direction substantially parallel to said axis X-X and, through its rotation, moves the coolant in a radial direction.
The movement of the impeller 2 is commanded by an electric motor 5, comprised in the pump group 1. Said electric motor 5 comprises a stator 51 and a rotor 52, operatively connected to the impeller 2 to drive it in rotation.
Preferably, the pump group 1 includes an impeller shaft 4 on which the impeller 2 is integrally connected and to which the electric motor 5 is operatively connected. Said impeller shaft 4 will be described in detail below.
The pump group 1 object of the present invention comprises a pump structure 10 that extends in height along the axis X-X. Preferably, the pump structure 10 is suitable to contain and support the impeller 2 and the electric motor 5.
According to the present invention, the pump structure 10 comprises a main body 100, an impeller body 200 and a fixing element 300.
The main body 100 is suitable to house the electric motor 5. The main body 100, in effect, defines internally a motor chamber 150 wherein is housed the electric motor 5, i.e. the stator 51 and the rotor 52.
According to the present invention, the main body 100 extends along the axis X-X, defining two axial ends, a first side 110 and a second side 120.
Preferably, the main body 100 has on its first side 110 an access opening allowing access to the motor chamber 150, whereas on the second side 120 it has a closure or bottom wall. According to a preferred embodiment, the main body 100 is, therefore, substantially cup-shaped.
Preferably, the main body 100 is made of a metallic material, for example, selected from among aluminum alloys. In possible variant embodiments, the main body 100 is made of a plastic material, for example, PA66 and PPS.
According to a preferred embodiment, the main body 100 is made as a single integral piece.
The impeller body 200 is suitable to contain the impeller 2 and is suitable to engage the main body 100 on its first side 110. Preferably, the impeller body 200 is suitable to close the access opening on the first side 110 of the main body 100.
Preferably, the impeller body 200 is fluidically connectable to the ducts of a vehicle cooling system, having at least one inlet mouth 201, preferably axial, and at least one outlet mouth 202, preferably radial.
According to a preferred embodiment, the impeller body 200 comprises a first half-shell 210 and a second half-shell 220 defining an impeller chamber 250 wherein the impeller 2 is housed.
Preferably, the first half-shell 210 and the second half-shell 220 are shaped in such a way that they is insertable one onto the other in an axial direction to delimit the walls of the impeller chamber 250.
Preferably, the second half-shell 220 extends substantially radially relative to the axis X-X, having a substantially flat wall that defines the bottom of the impeller chamber 250. Alternatively, however, the first half-shell 210 is formed with a shape that defines the impeller volute and the inlet mouth 201 and outlet mouth 202 of the coolant.
According to a preferred embodiment, the first half-shell 210 is made of a plastic material, for example PA66 and PPS.
According to a preferred embodiment, the second half-shell 220 is made of a plastic material, for example PA66 and PPS.
The fixing element 300 is suitable to lock axially the main body 100 and the impeller body 200.
Preferably, the fixing element 300 is suitable to engage, inserted radially, the main body 100 and the first half-shell 210.
Preferably, the fixing element 300, inserted radially, is suitable to engage also the second half-shell 220.
In a preferred embodiment, the fixing element 300 is insertable radially into the impeller body 200 and the main body 100, snap-engaging with the latter.
According to a preferred embodiment, in effect, the main body 100 on the first side 110 has a collar 118 on which it is possible to fit the impeller body 200.
Specifically, the first half-shell 210 is insertable axially on the collar 118. Preferably, in effect, the first half-shell 210 comprises a first inserting ring 218 which is insertable onto the collar 118, preferably on the outside of the collar 118.
According to a preferred embodiment, the second half-shell 220 is also insertable axially on the collar 118. Preferably, in effect, the second half-shell 220 includes a second inserting ring 228 which is insertable onto the collar 118, preferably on the outside of the collar 118.
Preferably, with respect to the axis X-X, the collar 118, the first inserting ring 218, and the second inserting ring 228 are concentric to each other.
As shown by way of example in the accompanying figures, the collar 118, the first inserting ring 218 and the second inserting ring 228 are sized so as to complement each other to allow the aforesaid reciprocal axial insertion.
According to a preferred embodiment, the first inserting ring 218 and the second inserting ring 228 extend axially so that the second inserting ring 228 is insertable to the collar 118, whereas the first inserting ring 218 is insertable to the second inserting ring 228 in such a way as to define therebetween the impeller chamber 250.
Preferably, the fixing element 300 engages the collar 118 by snap-locking thereon, extending through the first inserting ring 218. Preferably, the fixing element 300 extends also through the second inserting ring 228.
In effect, according to a preferred embodiment, the main body 100, the first inserting ring 218, and possibly also the second inserting ring 228, are designed in their geometry to allow this engagement of the fixing element 300 in such a way that the main body 100 and impeller body 200 are reciprocally axially locked.
According to a preferred embodiment, the collar 118 has a fastening recess 119 wherein the fixing element 300 is suitable to be housed. Preferably, said fastening recess 119 extends circumferentially along the entire collar 118. Preferably, the fastening recess 119 is positioned in such a way as to turn its opening outwards.
According to a preferred embodiment, the first inserting ring 218 comprises a first pair of reciprocally diametrically opposed slits 219.
Preferably, also the second inserting ring 228 comprises a second pair of reciprocally diametrically opposed slits 229.
According to such preferred embodiment, in an insertion configuration wherein the second inserting ring 228 and the first inserting ring 218 are inserted on the collar 118, the first pair of slits 219 and the second pair of slits 229 are in the same angular position (in other words, aligned angularly, in still other words, aligned radially) and allow the insertion of the fixing element 300. Preferably, the first pair of slits 219 and the second pair of slits 229 are at the same axial height as the fastening recess 119.
According to a preferred embodiment, the fixing element 300 has a central body 310 from which two locking arms 315 extend, suitable to snap-engage onto the main body 100. Preferably, said central body 310 is grippable in the operations of insertion and removal.
In other words, the fixing element 300 has a substantially 'U' or 'C' shape.
Preferably, the main body 100 and the impeller body 200 are housed in the space defined between the locking arms 315.
According to a preferred embodiment, according to that which is described above, said locking arms 315 are suitable to be housed in the fastening recess 119 of the collar 118 and/or in the slits of the first half-shell 210 and/or the second half-shell 220.
According to a preferred embodiment, the two locking arms 315 are specially designed to permit the radial insertion of the fixing element 300 on the main body 100 and to be clamped thereto in a locked position.
According to a preferred embodiment, each locking arm 315 has a sliding wall 315' suitable to allow the insertion of the fixing element 300 onto the main body 100 and a locking concavity 315" wherein the main body 100 is housed.
In other words, when the fixing element 300 is inserted in the radial direction onto the main body 100 and the impeller body 200, the following is discerned:

a first moment wherein each locking arm 315 engages the main body 100 with the sliding wall 315'; the sliding wall 315' is, in effect, specially shaped to undergo a pushing action that moves the two locking arms 315' away from each other, cooperating with the insertion operation;
a second moment, wherein upon reaching the end of the sliding wall 315', the main body 100 is in a position wherein it radially faces the locking concavity 315"; in such position, therefore, the main body 100 is accommodated in the locking recesses 315" in such a way that the two arms, undergoing no action, return to their starting position, snap-closing onto the main body 100.

The operation of removing the fixing element, on the contrary, involves the same moments in reverse order.
Preferably, the locking arms 315 are specially shaped to fit into the fastening recess and in the slits provided. Similarly, preferably, each locking concavity 315 is shaped in a manner complementary to the fastening recess 119 of the collar 118.
According to a preferred embodiment, as shown by way of example in the accompanying drawings, the height of the fixing element 300 and in particular of its locking arms 315, and in particular of the portion thereof known as the locking concavity 315", is substantially equal in height (net of geometric tolerances) to the walls which define the height of the housing recess 119 and the first pair of slits 219 and the second pair of slits 229: the fixing element 300, inserted on the main body 100 and on the impeller body 200, is therefore suitable to prevent an axial movement of the various components.
According to the object of the present invention, moreover, the second half-shell 220 comprises a tubular element 222 which extends inside the motor chamber 150 along the axis X-X, i.e. on the opposite side with respect to the side whereon the impeller 2 is placed.
Said tubular element 222 extends in length between the first and second sides of the main body 100. For example, in an embodiment wherein said second side 120 is a bottom wall, the tubular element 222 engages said bottom wall (which, for example, is specially shaped with a special annular stop). In other embodiments, the tubular element 222 is instead suitable to engage a special closing element of the opening provided on the second side 120.
Preferably, the tubular element 222 divides the motor chamber 150 into a stator chamber 151, wherein the stator 51 is housed, and a rotor chamber 152, wherein, instead, the rotor 52 is housed.
According to a preferred embodiment, the rotor chamber 152 is wet and the stator chamber 151 is dry. Preferably, the rotor 52 is of the wet rotor type.
According to a preferred embodiment, the second half-shell 220 has passage holes 225 suitable to allow the passage of coolant from the impeller chamber 250 to the rotor chamber 152 to fill the latter with coolant, until making contact with the second side 120.
According to a preferred embodiment, the impeller shaft 4 extends in length along the axis X-X in the impeller chamber 152. Preferably, in effect, the impeller shaft 4 has an impeller end 42 to which is fixed the impeller 2, housed, therefore, in the impeller chamber 250. Moreover, the impeller shaft 4 comprises a bottom end 41 engaged rotationally with the second side 120; the impeller shaft 4 is supported rotationally by the second side 120 and the second half-shell 220.
According to a preferred embodiment, the impeller shaft 2, between the two described ends, has a motor portion 45 whereon is mounted the rotor 51.
According to a preferred embodiment, the pump structure 10 according to the present invention comprises a minimum number of gaskets. Preferably, the pump structure 10 further comprises a first gasket 61 positioned between the first half-shell 210 and the second half-shell 220 and a second gasket 62 positioned between the second half-shell 220 and the main body 100. Preferably, the pump structure 10 comprises a third gasket 63 located between the tubular element 222 and the second side 120.
According to a preferred embodiment, the pump group 1 object of the present invention also comprises a command chamber suitable to contain electric command means commanding the electric motor 5 as needed. Preferably, said command chamber (not represented in the accompanying figures) is positioned on the second side 120. In a preferred embodiment where the second side 120 is a back wall, said command chamber is located on the opposite side relative to that of the housing chamber 150.
Preferably, said command chamber is delimited by the second side 120 and by a lid removably mounted thereon. In other embodiments, the command chamber is delimited by a specially shaped command body.
Other unrepresented variant embodiments of the pump group 1 object of the present invention and which share the same inventive concept are also possible. For example, in some preferred embodiments, the second half-shell 220 is fully joined to the first half-shell 210 and the latter is fitted to the main body 100 and fixed thereto by means of the fixing element 300, according to the above description. Similarly, in some preferred embodiments, the second half-shell 220 is fully joined to the main body 100 and the first shell 210 is fitted to the main body 100 and fixed thereto by means of the fixing element 300, according to the description above.
Innovatively, the pump group object of the present invention solves the problems that afflict the pump group solutions typical of the prior art.
Advantageously, the pump group object of the present invention has a simple structure.
Advantageously, the pump group object of the present invention has intuitive and immediate assembly/disassembly operations. Advantageously, the main body and the impeller body are reciprocally snap-locked to each other in a single insertion operation. Advantageously, the main body and impeller body may be unlocked from each other in a single removal operation. Advantageously, by means of a single "clip" element, i.e. the fixing element, the main body and the impeller body are locked axially.
Advantageously, the impeller body may be designed and produced using a plastic material, allowing the designer a meticulous design of the components: advantageously, in effect, the tubular element has a thickness reduced to a minimum, improving the performance of the electric motor; advantageously, the impeller body consists of two half-shells in such a way that as needed, the designer is free to design the best shape of the first shell, including one or more inlet and/or outlet mouths or a specific volute.
Advantageously, moreover, the pump unit is extremely modular and flexible.
Advantageously, the main body consists of one piece ensuring the robustness and reliability of the pump group itself.
It is clear that a person skilled in the art, in order to meet contingent needs, may make changes to the pump assembly, which may be contained within the scope of protection which is defined by the following claims.

Claims

Pump group (1) for a cooling circuit of a vehicle, comprising an impeller (2) rotating around an axis (X-X) and an electric motor (5) having a stator (51) and a rotor (52) operatively connected to the impeller (2) for driving it in rotation, wherein the pump group (1) comprises a pump structure (10) extending along the axis (X-X) to contain the impeller (2) and the electric motor (5), wherein the pump structure (10) comprises:
- a main body (100) defining internally a motor chamber (150) adapted to house the electric motor (5), wherein the main body (100) extends along the axis (X-X) having axially a first side (110) and a second side (120);

- an impeller body (200) suitable to engage the main body (100) on its first side (110), wherein the impeller body (200) comprises a first half-shell (210) and a second half-shell (220) defining an impeller chamber (250) wherein the impeller (2) is housed, wherein the second half-shell (220)
comprises a tubular element (222) extending along the axis (X-X) from the first side (110) to the second side (120), dividing the motor chamber (150) into a stator chamber (151) and a rotor chamber (152);

- a fixing element (300) adapted to axially lock the main body (100) and the impeller body (200);
wherein the pump group (1) is characterized by the fact that the fixing element (300) is insertable radially into the impeller body (200) and into the main body (100), engaging the latter by snap.
Pump group (1) according to claim 1, wherein the fixing element (300) has a central body (310), grippable by a user, wherefrom extend two locking arms (315) adapted to engage the main body (100) by snap.
Pump group (1) according to claim 2, wherein the two locking arms (315) are specially designed to permit the radial insertion of the fixing element (300) on the main body (100) and to be clamped to it in a locked position.
Pump group (1) according to claim 3, wherein the two locking arms (315) have a sliding wall (315') suitable to allow the insertion of the fixing element (300) on the main body (100) and a locking concavity (315") wherein the main body (100) is housed in a clamping configuration.
Pump group (1) according to any one of the preceding claims, wherein the main body (100) on the first side (110) has a collar (118) whereon the first half-shell (210) is axially insertable with a first inserting ring (218) concentric to said collar (118).
Pump group (1) according to claim 5, wherein also the second half-shell (220) is axially insertable on the collar (118) having a second inserting ring (228) concentric to said collar (118) and to said first inserting ring (218).
Pump group (1) according to claims 5 or 6, wherein the fixing element (300) engages the collar (118) through the first inserting ring (218) and possibly through the second inserting ring (228), snap-locking onto it.
Pump group (1) according to claim 7, wherein the collar (118) has a fastening recess (119) wherein the fixing element (300) is suitable to be housed.
Pump group (1) according to any one of the claims 5 through 8, wherein the first inserting ring (218) comprises a first pair of reciprocally diametrically opposed slits (219) allowing the insertion of the fixing element (300) for engaging the collar (118).
Pump group (1) according to claim 9 in combination with any of claims 6 through 8, wherein the second inserting ring (228) comprises a second pair of reciprocally diametrically opposed slits (229) in a manner such that in a configuration of insertion wherein the first inserting ring (218) and the second inserting ring (228) are inserted on the collar (118), the first pair of slits (219) and the second pair of slits (229) are angularly aligned and allow the insertion of the fixing element (300) .
Pump group (1) according to any one of the preceding claims, wherein the pump structure (10) further comprises a first gasket (61) positioned between the first half-shell (210) and the second half-shell (220) and a second gasket (62) positioned between the second half-shell (220) and the main body (100).
Pump group (1) according to any one of the preceding claims, wherein the second half-shell (220) has passage holes (225) adapted to allow the passage of coolant from the impeller chamber (250) to the rotor chamber (152) in a manner such that the rotor chamber (252) is wet and the stator chamber (251) is dry.
Pump group (1) according to any one of the preceding claims, further comprising an impeller shaft (4) extending along the axis (X-X) having an impeller end (42) to which the impeller (2) is fixed, a bottom end (41) rotatably engaged with the second side (120) and, between the two ends, a motor portion (45) whereon the rotor (51) is mounted.
Pump group (1) according to any one of the preceding claims, wherein the main body (100) has on its first side (110) an access opening allowing access to the motor chamber (150), while on the second side (120) it has a closure wall.