"Adjustable cooling pump for internal combustion engine" .

[0001] The present invention relates to an adjustable cooling pump for a cooling circuit of an internal combustion engine and the cooling circuit comprising it.

[0002] In the automotive and motorcycle sector, solutions aimed at regulating the cooling method of the combustion engine and/or other components comprised in the vehicles have already been known of for some time

[0003] Specifically, it is known how in some phases, such as starting the engine, the cooling thereof is not necessary or is required to a lesser extent.

[0004] In the known solutions, for example the solution claimed in BS2011A000150 in the name of the Applicant, it is known of to insert regulation components which reduce or completely obstruct the flow of coolant liquid to the pump rotor, so that the latter moves only a predefined amount of liquid.

[0005] Said embodiments, however, have always been designed in such a way that the actuation of said regulation components, and thus the flow of the liquid, was realised directly on the rotor, providing for components on the same and moved by its rotation shaft or moved through said rotation shaft.

[0006] Such embodiments present a plurality of drawbacks, among which the fact that this way the movement of said regulation components proves extremely complicated, complicating, in turn, the movement of the rotor; in the case in point, for example, the production of a hollow shaft through which to pass the drive means of the regulation component is required. Moreover, the direct movement of the rotation shaft of the rotor is complicated by the presence of the regulation component and the specific drive means thereof.

[0007] The purpose of the present invention is thus to provide an adjustable pump which resolves the problems of the prior art.

[0008] Said purpose is achieved by means of the adjustable pump claimed in claim 1, and by the cooling circuit as claimed in claim 16. The dependent claims show preferred embodiment variants entailing further advantageous effects .

[0009] The object of the present invention will be described in detail below with the help of the appended drawings, wherein: /

[0010] - figures 1 and la are two, in separate parts, perspective views showing the adjustable cooling pump which the present invention relates to, according to a possible embodiment;

[0011] -figures 2a, 2b and 2c are three transversal cross- sections of the pump as in figures 1 and la wherein the obturator cartridge comprised in said pump is respectively in a fully closed position, an intermediate position and a fully open position;

[0012] - figures 3 and 4 are two perspective views of the obturator cartridge comprised i-n the adjustable cooling pump which the present invention relates to, according to a preferred embodiment;

[0013] -figures 5 and 5a are respectively a side view and a transversal cross-section along the cartridge axis X-X of the obturator cartridge as in figures 3 and 4.

[0014] With reference to the above drawings, reference numeral 1 globally denotes an adjustable cooling pump according to a preferred embodiment variant of the invention.

[0015] Preferably, the adjustable cooling pump 1 is suitable to place in circulation a predefined quantity of coolant liquid in a cooling circuit of an internal combustion engine, for example of a motor vehicle or motorcycle. The adjustable cooling pump 1 which the present invention relates to is suitable to regulate the transit of coolant liquid to the engine and in particular is suitable to move a predetermined quantity of liquid according to need; in other words, the cooling pump 1 depending on the temperature of the coolant liquid and the phase of the motor (for example, if this is in the starting phase, or if it is already fully operational) permits the adjustment of the quantity of coolant liquid in circulation.

[0016] According to a preferred embodiment, the pump 1 comprises a pump body 2 comprising upstream at least one entry channel 21, 21' and downstream an exit channel 22; from the entry channel 21, 21' a predefined quantity of fluid enters the pump body 2 to then exit from the exit channel 22.

[0017] The pump 1 further comprises a rotor 3 placed in a rotor chamber 20 made in the pump body 2 between said channels, suitable for moving said coolant liquid through the exit channel 22. Preferably, the rotor 3 is of the radial type, the entry channel 21, 21' reaches the front of the radial rotor 3, while the output channel 22 is positioned circumferentially tangentially thereto.

[0018] Preferably, the cooling circuit also comprises a differentiated cooling circuit, for example specifically for cooling different components other than the combustion engine cooled by the primary circuit; consequently between the entry channels 21 a by-pass channel 21 ' is also comprised, part of said differentiated cooling circuit.

[0019] Preferably, a shaft 5 is connected to the rotor 3 suitable for placing said rotor 3 in rotation.

[0020] According to a preferred embodiment, in fact, the rotor 3 is connected to one end of the shaft 5 while at the other end, the drive means are connected, for example a pulley 50 and a belt, as in the appended drawings, and/or an electric motor (not shown), or the electric motor with adjustable rotation (not shown) directly.

[0021] According to a preferred embodiment, the pump 1, comprises regulation means 10 to regulate the flow towards the rotor 3 suitable to regulate the flow of coolant liquid to the rotor, and thus the circulation in the cooling circuit, depending on the cooling requirements of the engine and/or preferably, the temperature of the coolant liquid.

[0022] According to a preferred embodiment, the regulation means 10 comprise an obturator cartridge 100 specifically for the aforesaid purpose. Specifically, said cartridge 100 is axially translatable and depending on its axial position is suitable to regulate the passage of coolant liquid, for example reducing or obstructing it.

[0023] Preferably, the cartridge 100 is placed on the opposite side of the rotor 3, in other words on the opposite side to the shaft 5, preferably at least partially in the entry channel 21.

[0024] In other words, the cartridge 100 is composed of a single integral piece partially housed in the rotor chamber 20 and partially housed in the entry channel 21.

[0025] In fact, the cartridge 100 has an obturator portion 110 interacting with the coolant liquid substantially housed in the rotor chamber 20 and a guide portion 120 substantially housed in the entry channel 21 and engaged therewith to guide the translation of the obturator cartridge 100. The guide portion 120, in fact, is suitable to engage the inner rims 210 of the entry, channel 21 as a guide in translation.

[0026] According to a preferred embodiment, the rotor chamber 20 has an entry mouth 20 for the fluidic communication with the entry channel 21; in other words the rotor chamber 20 has an entry mouth of the incoming liquid from the entry channel. Preferably therefore the obturator cartridge 100 is suitable to obstruct said entry mouth 20' or suitable, moved on command, to reduce the through cross-section.

[0027] In the case in point in fact the cartridge 100 is translatable between a fully closed position in which the obturator portion 110 substantially obstructs the entry mouth 20', a plurality of intermediate positions in which the obturator portion 110 is distanced from the entry mouth 20' and a fully open position corresponding to the maximum distance of the obturator portion 110 from the entry mouth 20' .

[0028] Preferably, the obturator portion 110 has greater dimensions than the entry channel 21 and in particular the entry mouth 20', so that depending on its axial position the obturator 110 is suitable to obstruct the through cross-section of the entry channel 21 engaging the rims of the entry mouth 20' . The guide portion 120 instead has substantially complementary dimensions to the entry channel 21 extending close to an inner surface thereof .

[0029] According to a preferred embodiment, the obturator cartridge 100 extends in length.

[0030] Preferably, the obturator cartridge 100 extends with an axial-symmetric extension, for example around a cartridge axis X-X.

[0031] Preferably, the guide portion 120 has an annular extension .

[0032] In addition, the guide portion 120 is preferably joined to the obturator portion 110 by ribs 122 which extend along the cartridge axis X-X. Between two consecutive ribs 122, the obturator portion 110 and the guide portion 120 identify a through space 101 through which the coolant liquid is suitable to pass when the cartridge 100 is not in the fully closed position.

[0033] Preferably thus circumferentially, between the obturator portion 110 and the guide portion 120 a plurality of through spaces 101 are present interspersed by the ribs 122.

[0034] Therefore, depending on the position of the cartridge 100 in the entry channel 21, said through space 101 overlooks the side surface of the entry channel 21 or is partially or completely in the rotor chamber 20.

[0035] In other words, the lateral rims of the entry channel 21, depending on the axial position of the cartridge 100, act as a "dam" to the flow of coolant liquid through the through space 101.

[0036] According to a preferred embodiment, the rotor 3 has a front cavity 30, central thereto, suitable for housing the obturator portion 110 of the cartridge 100.

[0037] Preferably, in fact, the front cavity 30 is suitable to contain the obturator portion 110, partially when the cartridge 100 is placed in the intermediate positions, while it is suitable to contain it in its entirety when the cartridge 100 is instead placed in the open position.

[0038] According to a preferred embodiment the side rims of the front cavity 30 are also suitable to be engaged by the sides of the obturator portion 110 so as to act as an axial guide.

[0039] In a preferred embodiment, the obturator portion 110 is shaped so as to facilitate the flow of liquid to the rotor 3 towards the exit channel 22, in the intermediate and fully open configurations of the obturator cartridge 100.

[0040] In other words, the obturator portion 110 is suitable to act as a stopper, but also to act as a flow conveyor being suitable to direct the coolant liquid toward the rotor 3 and specifically towards the blades 35 of the rotor.

[0041] According to a preferred embodiment, in fact, the obturator portion 110 comprises a diverter surface 115 which faces the entry mouth 20', suitable to direct the liquid to the rotor. In other words, the diverter surface 115 is inclined to the imaginary cross-section surface of the entry channel 21 or the area delimited by the entry mouth 20' in such a way that the liquid flows over it and is directed toward the rotor 3.

[0042] Preferably the diverter surface 115 has an angle of inclination a equal to the angle of attachment α' of the blades 35 of the rotor 3.

[0043] According to a preferred embodiment said diverter surface 115 is conical or a truncated-cone shape.

[0044] According to a preferred embodiment moreover the regulation means 10 comprise detection means 200 sensitive to the temperature of the liquid and command means 300 operatively connected to said detection means and to the obturator cartridge 100 so as to move it depending on the temperature on the detection means 200.

[0045] In other words, the detection means 200 are suitable to have at least a portion thereof in contact with the coolant liquid to be influenced by the temperature thereof.

[0046] Depending on the temperature to which the detection means 200 are subject, the positioning of the obturator cartridge 100 is controlled by means of the command means 300 in a preferred position among those which said cartridge 100 is suitable to assume, and thus permit the reduction or obstruction of the transit of coolant liquid towards the rotor 3.

[0047] Preferably, the command means 300 comprise a command rod 310, movable in translation and attached to the obturator cartridge 100 in such a way that the movement of the rod 310 corresponds to a movement of the obturator cartridge 100.

[0048] Preferably, in fact, said command rod 310 has one end connected to the cartridge 100 while the other end is operatively connected to the detection means 200.

[0049] According to a preferred embodiment said command rod 310, connected to the cartridge 100, extends along said cartridge axis X-X; preferably, the command rod 310 is suitable to be attached facing the diverter surface 115. [0050] Moreover, in a preferred embodiment, the detection means 200 comprise elastic return means 210, such as compression springs, coil springs or one or more cup springs, suitable to act on the command rod 310 to keep the command means 300 active, i.e. to keep the cartridge 100 in the closed position. Depending on the temperature of the coolant liquid therefore the detection means 200 are suitable to overcome the force of the elastic return means 210 moving the command rod 310.

[0051] According to a preferred embodiment, the adjustment means 10 comprise a thermostat 500.. Preferably, the thermostat is suitable to act as the detection means 200 so as to move the command rod 310 preferably connected to it .

[0052] According to a preferred embodiment, the regulation means 10 are housed inside the pump body 2, preferably in the entry channel 21 and in the rotor chamber 20. In other words, as described above, the obturator cartridge 100 has a portion housed in the entry channel 21 and another portion housed in the rotor chamber 20, while the other components, i.e., the detection means 200 (also in the embodiment comprising a thermostat) and the command means 300 are housed inside the entry channel 21 (see the figures showing the cross-section of the pump body by way of example) . Preferably, this way, the coolant liquid is suitable to act directly on said components.

[0053] Preferably, in some embodiments the detection means 200 are placed in other positions of the pump body 2, or even in other positions of the cooling circuit. In yet other embodiment variants, even the command means 300 have shapes and geometries different from those described above and are positioned differently in the pump body 2 or in generic forms in the cooling circuit; according to some embodiments, the detection 200 and command means 300 may be replaced by electrical or vacuum systems.

[0054] The present invention also relates to a cooling circuit of an internal combustion engine comprising a cooling pump 1 according to the above description.

[0055] Innovatively, the cooling pump and cooling circuit to which it is applied are suitable to resolve the problems of the prior art.

[0056] Advantageously, in fact, in the cooling pump according to the present invention, the regulation of the flow of liquid does not affect the operation of the rotor, which proves entirely disconnected and independent therefrom.

[0057] A further advantageous aspect is moreover due to the fact that in the cooling pump which the present invention relates to, the leakage phenomena of the coolant liquid are minimised, which instead typically afflict the solutions of the prior art.

[0058] Another advantage lies in the fact that, thanks to the cooling pump according to the present invention, the energy dispersion of all the components is substantially reduced and minimised; this way the dispersion of pollutants, such as carbon dioxide, are controllable and are minimisable.

[0059] Advantageously, the operation of the rotor may be achieved in multiple ways, for example by means of a pulley, or with one or more electric motors, thus making it possible to control the rotation efficiently and thus realising further energy savings.

[0060] Moreover, advantageously, the pump which the present invention relates to has a more compact shape and limited overall dimensions.

[0061] A further advantageous aspect lies in the simplicity and economy of the pump according to the present invention .

[0062] Yet a further advantageous aspect is that the obturator cartridge and in general the regulation means, do not rotate together with the rotor and therefore do not increase its inertia and in general the inertia of the cooling pump.

[0063] Advantageously, the cartridge proves extremely durable thus improving the life span of the product. [0064] A person skilled in the art may make variations to the aforesaid embodiments of the cooling pump and cooling circuit so as to satisfy specific requirements, replacing elements with others functionally equivalent. Such variants are also contained within the scope of protection as defined by the following claims.

[0065] In addition, each variant described as belonging to a possible embodiment may be realised independently of the other embodiments described.