EP3390786A1

EP3390786A1 - A flow distribution device between an oil pump and a engine

Info

Publication number: EP3390786A1
Application number: EP15828517.1A
Authority: EP
Inventors: Nicolas GRANOTTIER; Christophe CUTAYA
Original assignee: Volvo Truck Corp
Current assignee: Volvo Truck Corp
Priority date: 2015-12-16
Filing date: 2015-12-16
Publication date: 2018-10-24
Also published as: WO2017103638A1

Abstract

The invention relates to a flow distribution device (1) designed to be connected to an oil pump capable of supplying oil to an engine (102). The device (1) comprises a body (2) having: - a first port (21) for connection with an oil sump (103) and a second port (22) for connection with a pump inlet (51), an intake channel (11) being formed between said first and second ports (21, 22); - a third port (23) for connection with a pump outlet (52) and a forth port (24) for connection with the engine (102), a discharge channel (12) being formed between said third and fourth ports (23, 24); - a by-pass channel (13) connecting the intake channel (11) and the discharge channel (12); The device (1) further comprises a controlled valve (30) configured to move inside the device body (2) between: - a closed position, in which said valve (30) closes the by-pass channel (13); - and a maximum return position, in which said valve (30) allows a portion of the flow of oil entering the third port (23) to flow through the by-pass channel (13) and return to the second port (22).

Description

A flow distribution device between an oil pump and an engine

TECHNICAL FIELD

The invention relates to a flow distribution device designed to be connected to an oil pump capable of supplying oil to an engine. The invention further relates to an arrangement comprising a pump and such a flow distribution device, and to a vehicle comprising such an arrangement.

The invention can be applied in heavy-duty vehicles, such as trucks, buses, construction equipment, agricultural vehicles and passengers cars.

BACKGROUND

Internal combustion engines are equipped with an oil pump which is capable of sucking oil from an oil sump and of supplying oil under pressure to various components of the engine, for lubrication and cooling purposes, before oil returns to the oil sump.

Such an oil pump can be a mechanical pump driven by the engine crankshaft, the oil pump speed thus depending on the engine speed. Consequently, the higher the engine speed, the higher the oil flow supplied to the engine by the pump. However, at high engine speeds, the oil flow supplied by the pump can be much higher than the engine lubricating / cooling needs. This generates excessive and unnecessary fuel consumption.

One solution to this issue is to provide a variable oil pump. However, this entails additional costs and more complexity.

SUMMARY

An object of the invention is to improve engine fuel consumption related to the operation of the oil pump, without significantly increasing costs and/or significantly changing the engine architecture. To that end, and according to a first aspect, the invention concerns a flow distribution device designed to be connected to an oil pump capable of supplying oil to an engine. The device comprises a body having:

- a first port for connection with a suction pipe in liquid communication with an oil sump and a second port for connection with a pump inlet, an intake channel being formed between said first and second ports;

- a third port for connection with a pump outlet and a fourth port for connection with the engine, a discharge channel being formed between said third and fourth ports;

- a by-pass channel connecting the intake channel and the discharge channel.

The device further comprises a controlled valve having a valve member configured to move inside the device body between:

- a closed position, in which said controlled valve closes the by-pass channel;

- and a maximum return position, in which said controlled valve allows a portion (Qvmax) of the flow (Q) of oil entering the third port to flow through the by-pass channel and return to the second port.

Thus, by the provision of a controlled valve, the invention makes it possible to vary the proportion of oil sucked from the oil sump that is actually supplied to the engine, by adjusting the by-pass channel cross section, i.e. the amount of oil that flows back to the pump inlet. In other words, owing to the controlled valve, the oil flow supplied to the engine can be adapted to the current needs, and can be lower than the whole oil flow exiting the pump.

As a consequence, there is less counter pressure at the pump outlet, which results in less power consumption by the oil pump, and ultimately in fuel saving.

A significant advantage of the invention is that the flow distribution device can be designed as a kit which can be placed on an existing oil pump, therefore not requiring a change in the oil pump. The invention further avoids the use of a variable oil pump.

In an embodiment, the third and fourth ports are separate. For example, the third and fourth ports can be located on distinct sides of the device body, preferably on opposite sides of the device body. In an embodiment, the first and fourth ports are located on a same first side of the device body, and the second and third ports are located on a same and second side of the device body. For example, the first side and the second side of the device body are opposite sides of the device body.

In an embodiment, the first, second, third, and fourth ports are separate.

The intake channel and the discharge channel can be substantially parallel. For example, the first port substantially faces the second port, while the third port substantially faces the fourth port. In other words, the intake channel and the discharge channel can be substantially straight. Moreover, the controlled valve can be arranged in a valve channel, and said valve channel can be substantially parallel to the intake channel and the discharge channel. _ For example, the intake channel, the discharge channel, by-pass channel and/or valve channel is/are tubular.

In a non limitative embodiment, the device body is substantially L-shaped or substantially H-shaped.

The controlled valve can further be configured to be placed in at least one intermediate return position, between the closed position and the maximum return position, in which said valve allows a portion (Qv) of the flow of oil entering the third port to flow through the by-pass channel and return to the second port, with Qv < Qvmax.

The valve member can be configured to be placed in one intermediate return position among a plurality of intermediate return positions. For example, the plurality of intermediate return positions forms a continuous set of positions. Alternatively, the plurality of intermediate return positions can form a set of discrete positions - i.e. the valve member can be placed in one of a predetermined finite number of intermediate return positions.

In an embodiment, the controlled valve is inserted in a valve channel which is arranged inside the device body and which opens in the by-pass channel. The valve channel can further open outside the device body, for example to allow a connection to a wire for electric supply and/or for controlling the valve.

In an embodiment, the position of the controlled valve is controlled depending on at least one operating parameter, such as en engine speed, an engine load, an oil temperature, an oil pressure, a coolant temperature, etc.

The controlled valve can be a mechanical valve arranged to be controlled by the fluid pressure in a discharge pipe connected to the fourth port or the fluid pressure in an oil circuit or in an oil gallery of the engine.

The controlled valve can be a solenoid valve comprising an electric solenoid capable of displacing the valve member to adjust the oil flow in the by-pass channel.

The controlled valve can be a mechanical valve arranged to be controlled by the fluid pressure in a discharge pipe that is connected to the fourth port or by the fluid pressure in an oil circuit or in an oil gallery of the engine. The controlled valve can be a mechanical valve arranged to be controlled by a proportional electronic valve.

According to a first aspect, the invention concerns an arrangement comprising a pump and a flow distribution device as previously described, the device second port being connected to the pump inlet, and the device third port being connected to the pump outlet.

The pump can be a fixed displacement pump (or constant flow rate pump), insofar as, owing to the flow distribution device, there is no need to use a variable displacement pump.

The device can be adjacent and fastened to the pump. In other words, in this embodiment, the device second port is directly connected to the pump inlet, and the device third port is directly connected to the pump outlet. Alternatively, the device and the pump can be spaced apart, with the arrangement comprising an inlet pipe connecting the second port and the pump inlet, and an outlet pipe connecting the third port and the pump outlet.

The arrangement can further comprise an engine, the device fourth port being connected to the engine.

The arrangement can further comprise an electronic control device capable of receiving at least one operating condition and of controlling the controlled valve depending on said operating condition.

According to a third aspect, the invention relates to a vehicle comprising an arrangement as previously described.

Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.

In the drawings:

Fig. 1 is a perspective view of an arrangement including a flow distribution device according to an embodiment of the invention, fastened on an oil pump;

Fig. 2 is an exploded view of the arrangement of Fig. 1 ;

Fig. 3 is a view similar to Fig. 1 , with the flow distribution device being partially cut;

Fig. 4 is a sectional view of the flow distribution device of Fig. 1 ;

Fig. 5 is a perspective view of an arrangement including a flow distribution device according to another embodiment of the invention, fastened on an oil pump;

Fig. 6 is a sectional view of the flow distribution device of Fig. 5;

Fig. 7 is a schematic view of the operation of the controlled valve of the flow distribution device such as represented on figures 1 to 6;

Fig. 8 is a schematic view of the operation of the controlled valve of the flow distribution device according to another embodiment of the invention. DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

Figures 7 and 8 schematically show an arrangement 100 in a vehicle, the arrangement 100 comprising an engine 102, which is an internal combustion engine, and an oil pump 50. The pump 50 is designed to suck oil from an oil sump 103, through an oil strainer 104 and by means of a suction pipe 105 which is connected to the pump inlet 51. At least part of the oil exiting the pump outlet 52 is supplied to the engine 102 by means of a discharge pipe 106. The discharge pipe 106 can comprise a filter 107. After exiting the engine 102, oil flows back to the oil sump 103 by means of a return pipe 109. In practice, the pump 50 can be a mechanical pump driven by an engine crankshaft (not shown). In a preferred embodiment, the pump 50 is a fixed displacement pump.

According to the invention, the arrangement 100 further comprises a flow distribution device 1 which makes it possible to vary the proportion of oil sucked from the oil sump 103 that is actually supplied to the engine 102.

Such as represented on figures 1 to 6, the flow distribution device 1 comprises a body 2 which can be made of metal, such as steel. The body 2 comprises a first port 21 for connection with the oil sump 103, and a second port 22 for connection with the pump inlet 51. In practice, the first port 21 can be connected to the suction pipe 105, while the second port 22 can be connected to the pump inlet 51 either directly or via an inlet pipe. An intake channel 1 1 is formed between said first and second ports 21 , 22.

The body 2 also comprises a third port 23 for connection with the pump outlet 52 and a forth port 24 for connection with the engine 102. In practice, the third port 23 can be connected to the pump outlet 52 either directly or via an outlet pipe, while the forth port 24 can be connected to the discharge pipe 106. A discharge channel 12 is formed between said third and fourth ports 23, 24.

In the illustrated embodiments, the first port 21 , second port 22, third port 23 and fourth port 24 are separate. The body 2 further comprises a by-pass channel 13 which connects the discharge channel 12 and the intake channel 11.

The oil flows in the various pipes / channels are referenced as follows:

- Qin: flow in the suction pipe 105;

- Q: flow exiting the pump outlet 52 and entering the third port 23;

- Qv: flow in the by-pass channel 13, Qv being lower than Q;

- Qout: flow in the return pipe 109. As schematically illustrated in figures 7 and 8, the flow distribution device 1 further comprises a controlled valve 30 having a valve member 301 which is configured to move inside the device body 2 between:

- a closed position, in which said controlled valve 30 closes the by-pass channel 13;

- and a maximum return position, in which said controlled valve 30 allows a portion (Qv=Qvmax) of the flow Q of oil entering the third port 23 to flow through the by-pass channel 13 and return to the second port 22.

The controlled valve 30 is inserted and moveable in a valve channel 14 which is arranged inside the body 2, and which opens in the by-pass channel 13.

In practice, the controlled valve 30, more precisely its valve member 301 , can further be configured to be placed in one or several intermediate return positions, between the closed position and the maximum return position. In an intermediate return position of the valve member 301 , the controlled valve 30 allows a portion (Qv<Qvmax) of the flow of oil entering the third port 23 to flow through the by-pass channel 13 and return to the second port 22. The plurality of intermediate return positions can form a continuous set of positions or a discrete set of positions.

As schematically shown on figures 4 , 6 and 7, the arrangement 100 may further comprise an electronic control device 115 capable of receiving at least one operating condition and of controlling the controlled valve 30 depending on said operating condition. In other words, the position of the controlled valve 30, more precisely the position of its valve member 301 , can thus be controlled depending on at least one operating parameter. Said parameter can be an engine speed, an engine load, an oil temperature, an oil pressure, a coolant temperature, etc. As a result, the flow of oil actually supplied to the engine 102 can be determined and controlled depending on the actual current needs, for example in terms of lubrication and/or cooling of the engine components. More precisely, the flow supplied to the engine 102 is Q-Qv, with Qv being controlled by the position of the valve 30.

5

The valve control can be either a close loop control using an oil pressure sensor in the oil system, or an open loop control not requiring an oil pressure sensor.

In an embodiment, the controlled valve 30 is a solenoid valve, as depicted in figures 4, 6 10 and 7, for example. Then, the valve 30 is an electromechanically operated valve, the position of the valve member 301 is controlled, through an electric solenoid 34 such as represented on figures 4, 6 and 7, by means of the electronic control device 115. The electric solenoid 34 can control an open or a closed position of the valve member 301 and also intermediate positions of the valve member 301 between the open and the closed 15 positions. In such an embodiment, the controlled valve 30 directly controls the oil flow. A biasing means, such as a spring 37 configured to urge the valve member 301 in one direction, can further be provided to maintain the controlled valve 30 in its closed position or in its open position such as represented on figure 4 when the solenoid 34 is not energized. To ensure engine lubrication in case of malfunction of the solenoid valve, it is 20 preferred, such as represented on figure 7, to arrange the spring 37 such that it maintains the controlled valve 30 in its closed position when the solenoid valve is not energized or is malfunctioning.

In another embodiment represented on figure 8, the controlled valve 30 is a mechanical valve, which is controlled by a pressure feedback line 61 connecting the controlled valve

25 30 to a connection point 62 that is located downstream from the pump 50 in the discharge pipe 106 or in the engine 102 such as in an oil gallery (not represented) of the engine. A biasing means, such as a spring 37, can further be provided to maintain the controlled valve 30 in its closed position when pressure in the feedback line 61 is below a predetermined threshold pressure value and to define, above this predetermined

30 threshold pressure value, intermediate positions of the controlled valve 30, more precisely of the valve member 301 , depending on the pressure in the feedback line 61. The spring 37 is located in a spring chamber 39 of the controlled valve 30.

In the embodiment of figure 8, an electronic valve 36 is also provided. Open and closed positions of the electronic valve 36 are controlled by an electronic control device 115 that 35 authorizes or not the controlled valve 30 to be controlled by the pressure of the feedback line 61. The controlled valve 30 is authorized to be controlled by the pressure of feedback line 61 when the electronic valve 36 is in an open position where it connects the spring chamber 39 to the oil sump 103 through discharge pipes 65 and 66. The controlled valve 30 is not authorized to be controlled by the pressure of feedback line 61 when the electronic valve 36 is in a closed position which seals the spring chamber 39.

In another embodiment (not shown), the electronic valve 36 of the embodiment of figure 8, that is of the on/off type, is replaced by a proportional electronic valve. In this embodiment, the proportional electronic valve can be moved between two end positions - an open or a closed position- and can also be placed in intermediate positions between its open and closed positions. Depending on its degree of opening, the proportional electronic valve is able to deliver to the controlled valve a control pressure having a given value. The control pressure controls the position of the controlled valve 30, more precisely of its valve member 301. In this embodiment, the electronic control device 115 controls the proportional electronic valve (not shown) which in turn controlled the position of the controlled valve 30.

A biasing means, such as a spring, can further be provided to maintain the controlled valve in its closed position. The electronic control device 115 -through the proportional electronic valve - can make the controlled valve 30 move towards its maximum return position, against the force exerted by the spring.

A first embodiment of the invention will now be described with reference to figures 1 to 4. In this embodiment, the body 2 of the flow distribution device 1 is substantially L-shaped, as best shown in figures 2 and 4. It comprises a first branch 25 extending in a direction X, and a second branch 26 extending in a direction Y, said branches 25, 26 being substantially orthogonal. Direction Z is defined as the direction orthogonal to X and Y. The body 2 comprises two main opposite sides, namely a first side 28 and a second side 29, which in the disclosed embodiment are substantially parallel opposite faces of the body 2. Although these sides are generally not flat, they are substantially arranged orthogonally to direction Z. The first port 21 and the fourth port 24 are located on the first side 28, which forms an interface with the engine 102, while the second port 22 and third port 23 are located on the second side 29, which forms an interface with the pump 50. More precisely, the first port 21 and the second port 22 can be arranged near the free end of the first branch 25, and can be substantially aligned along Z, meaning that the intake channel 1 1 can be substantially straight and extend along Z. Similarly, the third port 23 and the fourth port 24 can be arranged near the free end of the second branch 26, and can be substantially aligned along Z, meaning that the discharge channel 12 can be substantially straight and extend along Z.

Moreover, the valve channel 14 can be arranged in the second branch 26, along direction Y, and can open both in the discharge channel 12 and outside the body 2. As regards the by-pass channel 13, it can be arranged in the first branch 25, along direction X, and can open both in the valve channel 14 and in the intake channel 1 1. As a consequence, the intake channel 1 1 and the discharge channel 12 can be in fluid communication by means of the by-pass channel 3 and of the valve channel 14. For design reasons, the by-pass channel 13 can further open towards the outside at the free end of the first branch 25. A plug 40 provided with a seal 41 can be arranged to close this end of the by-pass channel 13, as shown in figure 2.

The valve 30 is inserted in the valve channel 14 and can partially extend outside the body 2. In the illustrated embodiment, a housing 31 is secured to the body 2 by appropriate fasteners 32, where the valve channel 14 opens outside the body 2. Therefore, the housing 31 forms with the body 2 a substantially closed casing for the valve 30.

A connecting set 33 is provided for making it possible to control the valve displacement inside the valve channel 4. Said connecting set 33 can typically include cables and allows connecting the valve 30 to a device capable of controlling the valve 30, such as the electronic control device 1 15 or the electronic valve 36.

As can be seen on figures 1 -3, in the mounted position, the flow distribution device 1 is adjacent to the pump 50. In other words, the second port 22 of the flow distribution device body is connected to the pump inlet 51 without intermediary pipe, and the third port 23 of the flow distribution device body is connected to the pump outlet 52 without intermediary pipe. Although no intermediary pipe is provided, the junction between the pump 50 and the flow distribution device 1 may comprise sealing members. Moreover, the flow distribution device 1 is fastened to the pump 50 by means of appropriate fasteners 54.

The pump inlet 51 is connected to the oil sump 103 via the body 2 - and more specifically via the intake channel 1 1 - and the suction pipe 105, while the pump outlet 52 is connected to the engine 102 via the body 2 - and more specifically via the discharge channel 12 - and the discharge pipe 106.

In the preceding embodiments of the invention, instead of being connected directly to the pump 50, such as traditionally known from prior art, the suction pipe 105 and the discharge pipe 106 are connected to the body 2 of the flow control device 1 , on the first side 28 of said body 2. In this implementation, the pump architecture remains unchanged. The only change required to add the flow control device 1 in an existing arrangement is to shorten the suction pipe 105 and the discharge pipe 106 to allow sufficient place to install the flow control device 1. Alternatively, depending on the engine design, the suction pipe 105 and the discharge pipe 106 could be at least partially included in the flow control device 1.

In practice, the controlled valve 30, more precisely its valve member 301 , is maintained by the spring 37 in its closed position. Then, all the oil flow sucked by the pump 50 and exiting the pump 50 is directed to the engine 102 through the discharge channel 12 of the flow control device 1. Indeed, the by-pass channel 13 connecting the intake channel 1 1 and the discharge channel 12 inside the body 2 is closed by the controlled valve 30.

Depending on current operating conditions, for example at high engine speeds when the oil flow supplied to the engine is much higher than the engine needs, the control unit 115, in the embodiments of figures 1 to 7 and in the embodiment using a proportional electronic valve (not shown), or the pressure feedback line 61 , in the embodiment of figure 8, controls the controlled valve 30 to make it move inside the valve channel 14 towards the maximum return position. The valve can be placed in said maximum return position or in a suitable intermediate return position. In the - maximum or intermediate - return position, a portion Qv of the oil flow exiting the pump outlet 52 flows through radial openings 38 arranged in the valve 30 and the by-pass channel 13 to the intake channel 11 , and then back to the pump inlet 51 , i.e. is not directed to the engine 102.

In other words, the oil flow actually supplied to the engine 102 is regulated by the flow control device 1 , and can be lower than with a standard fixed displacement pump devoid of such a flow control device 1. Moreover, the oil flow in the pump is lower when such a flow control device is provided. Owing to the invention, as only the oil flow needed for the engine operation goes throughout the pump, less counter pressure is generated at the pump outlet, and the pump consumption is lower, which results in fuel saving.

A second embodiment of the invention will now be described with reference to figures 5 and 6.

In this embodiment, the body 2 of the flow distribution device 1 is substantially H-shaped, and comprises a first branch 25 extending in the X direction a second branch 26 extending in the Y direction, and a third branch 27 extending in the X direction.

The body 2 comprises two main opposite sides, namely a first side 28 and a second side 29, which in the disclosed embodiment are substantially parallel opposite faces of the body 2. Although these sides are generally not flat, they are substantially arranged orthogonally to direction Z.

The intake channel 11 extends along Y in the third branch 29, the first port 21 being located on the first side 28 and the second port 22 being located on the second side 29. The first port 21 and the second port 22 can be substantially aligned along Y, meaning that the intake channel 11 can be substantially straight.

The discharge channel 12 extends along Y in the first branch 25, the third port 23 being located on the second side 29 and the fourth port 24 being located on the first side 28. The third port 23 and the fourth port 24 can be substantially aligned along Y, meaning that the discharge channel 12 can be substantially straight.

The first side 28, on which are located the first port 21 and the fourth port 24, forms an interface with the engine 102, while the second side 29, on which are located the second port 22 and third port 23, forms an interface with the pump 50. Besides, the valve channel 14 can be arranged along direction Y, in a sleeve 35 protruding from the second branch 26 of the body 2, for example from the first side 28. The valve channel 14 can be arranged half way between the intake channel 11 and the discharge channel 12.

The by-pass channel 13 can be arranged in the second branch 26 of the body 2, and extend along direction X. In the exemplary embodiment, the by-pass channel 13 comprises a first portion 13a extending from the discharge channel 12 to the valve channel 14, and a second portion 13b extending from the valve channel 14 to the intake channel 11 , the portions 13a, 13b being offset along direction Y. The valve channel 14 can open both in the by-pass channel 13, here at the junction between first and second portions 13a, 13b, and outside the body 2. As a consequence, the intake channel 11 and the discharge channel 12 can be in fluid communication by means of the by-pass channel 13 and of the valve channel 14.

For design reasons, the by-pass channel 13 can further open towards the outside at both ends. A plug 40 provided with a seal 41 can be arranged to close each end of the by-pass channel 13, as shown in figure 6.

Similarly to figures 1-4, the valve channel 14 can open outside the body 2, and the controlled valve 30 can partially extend outside the body 2. In the illustrated embodiment, the controlled valve 30 is located in a casing formed by both the valve channel 14 and a housing 31 secured to the sleeve 35 of the body 2 by appropriate fasteners (not shown). A connecting set 33 allows connecting the valve 30 to a device capable of controlling the valve 30, such as the electronic control device 115 that controls position of the valve via, for instance, an electric solenoid 34 of the controlled valve 30.

Similarly to figures 1-4, in the mounted position, the flow distribution device 1 is adjacent to the pump 50 and fastened to the pump 50 by means of appropriate fasteners 54.

The pump inlet 51 is connected to the oil sump 103 via the body 2 - and more specifically via the intake channel 11 - and the suction pipe 105, while the pump outlet 52 is connected to the engine 102 via the body 2 - and more specifically via the discharge channel 12 - and the discharge pipe 106. The flow control device 1 is operated as follows:

- the valve 30 is maintained by the spring 37 in its closed position, letting all the oil flow exiting the pump 50 to be directed to the engine 102 through the discharge channel 12; - depending on current operating conditions, the control unit 1 5 (figures 1 to 7) or the pressure feedback line 61 (figure 8) controls the valve 30 to place it inside the valve channel 14 at a maximum or intermediate return position, in which a portion Qv of the oil flow exiting the pump outlet 52 flows through the by-pass channel 13 and radial openings 38 arranged in the valve 30 to the intake channel 11 , and then back to the pump inlet 51.

This allows regulating the oil flow actually supplied to the engine 102.

A significant advantage of the invention is that it makes it possible to change an arrangement having a fixed displacement pump into an arrangement operating as a variable pressure oil system, without impacting the current serial production pump design nor the engine architecture.

The invention allows offering a customer to easily upgrade his vehicle by the implementation of the flow distribution device between the pump and the engine, which brings a significant fuel consumption improvement.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.

Claims

1. A flow distribution device designed to be connected to an oil pump (50) capable of supplying oil to an engine (102), the device (1) comprising a body (2) having:

- a first port (21) for connection with a suction pipe (105) in liquid communication with an oil sump (103) and a second port (22) for connection with a pump inlet (51), an intake channel (11) being formed between said first and second ports (21 , 22);

- a third port (23) for connection with a pump outlet (52) and a fourth port (24) for connection with the engine (102), a discharge channel (12) being formed between said third and fourth ports (23, 24);

- a by-pass channel (13) connecting the intake channel (11) and the discharge channel (12);

the flow distribution device (1) further comprising a controlled valve (30) having a valve member (301) configured to move inside the device body (2) between:

- a closed position, in which said controlled valve (30) closes the by-pass channel (13);

- and a maximum return position, in which said controlled valve (30) allows a portion (Qvmax) of the flow (Q) of oil entering the third port (23) to flow through the by-pass channel (13) and return to the second port (22).

2. The flow distribution device according to claim 1 , characterized in that the third and fourth ports (23, 24) are separate.

3. The flow distribution device according to claim 2, characterized in that the third and fourth ports (23, 24) are located on distinct sides (28, 29) of the device body (2), preferably on opposite sides of the device body (2).

4. The flow distribution device according to any one of claims 1 to 3, characterized in that the first and fourth ports (21 , 24) are located on a same first side (28) of the device body (2), and in that the second and third ports (22, 23) are located on a same and second side (29) of the device body (2).

5. The flow distribution device according to claim 4, characterized in that the first side (28) and the second side (29) of the device body (2) are opposite sides of the device body (2).

6. The flow distribution device according to any one of claims 1 to 5, characterized in that the intake channel (11) and the discharge channel (12) are substantially parallel.

7. The flow distribution device according to claim 6, characterized in that the controlled valve (30) is arranged in a valve channel (14), said valve channel (14) being substantially parallel to the intake channel (11) and the discharge channel (12).

8. The flow distribution device according to any one of claims 1 to 7, characterized in that the device body (2) is substantially L-shaped or substantially H-shaped.

9. The flow distribution device according to any one of claims 1 to 8, characterized in that the valve member (301) is further configured to be placed in at least one intermediate return position, between the closed position and the maximum return position, in which said valve (30) allows a portion (Qv) of the flow of oil entering the third port (23) to flow through the by-pass channel (13) and return to the second port (22), with Qv < Qvmax.

10. The flow distribution device according to claim 9, characterized in that the valve member (301) is configured to be placed in one intermediate return position among a plurality of intermediate return positions.

11. The flow distribution device according to claim 10, characterized in that the plurality of intermediate return positions forms a continuous set of positions.

12. The flow distribution device according to any one of claims 1 to 11 , characterized in that the controlled valve (30) is inserted in a valve channel (14) which is arranged inside the device body (2) and which opens in the by-pass channel (13).

13. The flow distribution device according to claim 12, characterized in that the valve channel (14) further opens outside the device body (2).

14. The flow distribution device according to any one of claims 1 to 13, characterized in that the position of the controlled valve (30) is controlled depending on at least one operating parameter, such as en engine speed, an engine load, an oil temperature, an oil pressure, a coolant temperature, etc.

15. The flow distribution device according to claim 14, characterized in that the controlled valve (30) is a solenoid valve comprising an electric solenoid (34) capable of displacing the valve member (301 ) to adjust the oil flow (Qv) in the by-pass channel (13).

5 16. The flow distribution device according to claim 14, characterized in that the controlled valve (30) is a mechanical valve arranged to be controlled by the fluid pressure in a discharge pipe (106) that is connected to the fourth port (24) or by the fluid pressure in an oil circuit or in an oil gallery of the engine (102).

10 17. The flow distribution device according to claim 14, characterized in that the controlled valve (30) is a mechanical valve arranged to be controlled by a proportional electronic valve.

18. An arrangement comprising a pump (50) and a flow distribution device (1 ) according 15 to any one of claims 1 to 16, the device second port (22) being connected to the pump inlet (51), and the device third port (23) being connected to the pump outlet (52).

19. The arrangement according to claim 18, characterized in that the pump (50) is a fixed displacement pump.

20

20. The arrangement according to claim 18 or 19, characterized in that the device (1 ) is adjacent and fastened to the pump (50).

21. The arrangement according to claim 18 or 19, characterized in that the device (1) and 25 the pump (50) are spaced apart, and in that the arrangement (100) comprises an inlet pipe (111) connecting the second port (22) and the pump inlet (51), and an outlet pipe (112) connecting the third port (23) and the pump outlet (52).

22. The arrangement according to any one of claims 18 to 21 , characterized in that it 30 further comprises an engine (102), the device fourth port (24) being connected to the engine (102).

23. The arrangement according to any one of claims 18 to 22, characterized in that it further comprises an electronic control device (115) capable of receiving at least one operating condition and of controlling the controlled valve (30) depending on said operating condition.

24. A vehicle, characterized in that it comprises an arrangement (100) according to any one of claims 18 to 23.