FR3040563A1 - SYSTEM FOR A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a system (1) for a motor vehicle, said system comprising: - an electric machine (3) configured to provide torque to an internal combustion engine of the vehicle, in particular for starting the internal combustion engine (4) of the vehicle, - a cooling circuit (50) of the machine arranged to cool this machine and / or a power electronics associated with this machine, this cooling circuit being connected to an air conditioning device (51) of the vehicle.

Description

System for a motor vehicle

The present invention relates to a system for a motor vehicle, in particular a truck or a bus.

US Pat. No. 6,823,690 and Patent Application JP9324668 disclose an air conditioning compressor. The invention aims to improve this type of system. The invention thus relates to a system for a motor vehicle, this system comprising: an electric machine configured to provide a torque to an internal combustion engine of the vehicle, in particular for starting the internal combustion engine of the vehicle; cooling of the machine arranged to cool the machine and / or a power electronics associated with this machine, this cooling circuit being connected to an air conditioning device, also called air conditioning device, of the vehicle.

Thanks to the invention, it is possible to increase the electric power of the electric machine because this well cooled machine can produce more electrical power. The invention also allows to take advantage of a simple cooling circuit, namely connected to the air conditioning device present on the vehicle, to cool the electric machine. For example, it is not necessary to provide an additional pump, for example a water pump, to cool the electric machine since it is possible to use the air conditioning device already present on the vehicle.

It is thus possible to avoid having a specific water cooling for the machine.

Preferably, the electric machine is reversible so that, in addition to being able to provide a torque to the combustion engine, be able to operate as an alternator driven by the combustion engine.

In an exemplary implementation of the invention, the machine is further configured to mechanically operate equipment formed by a compressor, including the air conditioning device.

Advantageously, the equipment is configured to be able to operate with the electric machine when the combustion engine of the vehicle is at a standstill.

Preferably, the air conditioning device comprises in addition to the cooling circuit of the electric machine, a ventilation circuit arranged to selectively ventilate hot air or cold air in the passenger compartment.

Advantageously, the cooling circuit of the electric machine and the ventilation circuit of the passenger compartment are arranged to use the same compressor of the air conditioning device.

In an exemplary implementation of the invention, the cooling circuits of the machine and the passenger compartment are connected in series.

The air conditioning device can use a heat transfer fluid capable of changing state, in particular from a gaseous state to a liquid state and vice versa.

Advantageously, the air conditioning device comprises a condenser through which the heat transfer fluid can circulate, this condenser being arranged to condense the coolant from the gaseous state to the liquid state.

The air conditioning device advantageously comprises an evaporator through which the heat transfer fluid can circulate, this evaporator being arranged to evaporate the coolant from the liquid state to the gaseous state. The evaporator is used to cool the air that is sent into the cabin.

If desired, the air conditioning device comprises an expansion valve through which the heat transfer fluid can circulate, this expansion valve being arranged to expand the coolant which is in the liquid state, the temperature of the heat transfer fluid dropping so.

The air conditioning device is arranged to allow cooling of the heat transfer fluid to a temperature lower for example at 10 ° C, especially below 5 ° C.

The electrical performance of the electric machine is advantageously increased due to the cooling allowed by the cooling circuit.

The cooling circuit of the machine is arranged to cool the machine also when the machine operates as an alternator, this machine being then driven by the internal combustion engine of the vehicle. This increases the electrical performance of the machine during this phase of electricity production and also allows the machine to debit more power in the regenerative braking phase. The invention also relates to a method of cooling an electric machine configured to provide torque to an internal combustion engine of the vehicle, in particular for starting the internal combustion engine of the vehicle: - Cooling the machine with a cooling circuit of the machine arranged to cool the machine, this cooling circuit being connected to a vehicle air conditioning device.

Preferably, the electric machine is reversible so that, in addition to being able to start the combustion engine, be able to operate as an alternator driven by the combustion engine. In other words, the electric machine makes it possible to perform the Stop-Start function, to automatically restart the combustion engine at the end of an automatic stop phase, phase also called "Idling Stop" in English.

This automatic stopping phase corresponds for example to a stop at a red light, and the combustion engine is restarted when the driver presses the accelerator pedal.

Thus in the automatic stop phase or "Idling Stop", the combustion engine is stopped, the reversible electric machine can operate the equipment that otherwise would also be stopped. The invention is particularly advantageous for a truck or a bus.

When the machine operates as an alternator, this reversible machine produces electric current that charges a battery of the vehicle. The invention makes it possible to dispense with the use of electrified and autonomous equipment.

The electric machine has in particular an electric power of between 4 and 25 KWatts, in particular between 6 and 12 KWatts, in particular a power substantially equal to 8 KWatts. This type of machine is for example a machine driven belt.

The electric machine is, if desired, configured to generate electric current during braking of the vehicle engine. This allows regenerative braking.

If necessary, the electric machine is configured to assist the combustion engine when the latter is in operation.

According to the invention, the equipment is configured to operate with the electric machine when the combustion engine is stopped. If the equipment is an air conditioning compressor, this allows the air conditioning of the cabin even during phases of automatic shutdown or "Idling Stop". The equipment comprises a rotary member, in particular rotary shaft, this rotary member having an axis of rotation offset from the axis of rotation of the electric machine.

When the equipment is a compressor, the rotary shaft is operated for compressed air.

Advantageously, the rotary member of the equipment is configured so that it can selectively: - be decoupled in rotation from both the combustion engine and the electrical machine so as to be at rest, - be rotated by the combustion engine, - be rotated by the electric machine.

Thanks to the invention, it is not necessary to have a motor dedicated to the compressor. This allows for a relatively simple architecture.

Preferably, the rotary member, in particular the rotary shaft, of the equipment is associated with a drive member, in particular a pulley, which is selectively coupled and decoupled with respect to the rotary member, so that that when the drive member is coupled with the rotary member, these two members rotate together, and when the drive member is decoupled from the rotary member, the drive member can rotate without causing the rotary member.

Advantageously the drive member of the equipment is rotated systematically when the electric machine rotates. In other words, the drive member of the equipment can not be idle when the electric machine is running.

In an exemplary implementation of the invention, the equipment comprises a clutch, in particular an electromagnetic clutch, arranged to selectively couple and decouple the drive member and the rotary member of the equipment.

Preferably, the electric machine comprises a first drive member associated with the internal combustion engine and a second drive member associated with the equipment, the two members being able to be selectively secured in rotation or disengaged in rotation.

Advantageously, the two drive members being interconnected by a clutch, in particular an electromagnetic clutch, arranged to selectively couple and decouple the two drive members.

In an exemplary implementation of the invention, at least one of the drive members comprises a pulley, in particular the two drive members each comprise a pulley.

The electric machine and the combustion engine are in particular coupled by a first transmission belt, which is in particular mounted on the first drive member.

The electrical machine and the equipment are in particular coupled by a second transmission belt, which is in particular mounted on the second drive member of the electric machine.

If necessary, it is possible to replace the drive belt by a contact between two meshing elements.

In an exemplary implementation of the invention, this second belt is mounted on the second drive member of the electric machine and on the drive member of the equipment so that these drive members are connected. constantly rotating.

The first and second transmission belts are distinct. The equipment is advantageously arranged to operate solely with the help of the electric machine and the combustion engine, the equipment being in particular devoid of dedicated electric motor.

The combustion engine comprises a drive member, in particular a pulley cooperating with the first transmission belt.

Preferably, the system arranged so that, in a first mode of operation: - The electromagnetic clutch is closed so that the two drive members are coupled in rotation - The combustion engine drives the two bodies coupled drive, the drive member of the electrical machine driving the equipment including via the drive member of the equipment. Thus the electric machine operates as an alternator and the compressor is in operation.

The system is arranged in such a way that, in a second mode of operation: the combustion engine is at a standstill, in particular in an automatic stopping phase, the electric machine operates as a motor, and the clutch between the two drive members of the machine is open, the two drive members being thus uncoupled, - On the machine, the drive member drives the equipment, and the uncoupled drive member does not drive not the combustion engine. Thus the compressor is in operation while the combustion engine is stopped.

The system is arranged so that, in a third mode of operation: - The combustion engine is in operation and drives the electric machine which acts alternator, - The clutch on the electric machine is closed, - The Clutch on the equipment is open so that the drive on the equipment rotates without driving the rotating shaft of the equipment. Thus the compressor is stopped.

The system is optionally arranged to equip a truck or a bus. The invention further relates to a system comprising: an electrical machine configured to provide a torque to an internal combustion engine of the vehicle, in particular for starting the internal combustion engine of the vehicle, a cooling circuit of the machine arranged to cool this machine and / or a power electronics associated with this machine, this cooling circuit being connected to a vehicle air conditioning device so that the air conditioning device selectively delivers hot air or cold air to the passenger compartment of the vehicle.

Preferably, the air conditioning device comprises a reversing valve (or reversing valve in English) connected to an outlet of the compressor so as to direct the heated fluid from the compressor selectively to the condenser or the ventilation circuit.

Advantageously, the ventilation circuit is arranged to ventilate the passenger compartment with air heated by the coolant when the inversion valve directs the heat transfer fluid from the compressor directly to the ventilation circuit without passing through the condenser.

Still advantageously the ventilation circuit is arranged to ventilate cooled air in the passenger compartment when the inversion valve directs the heat transfer fluid from the compressor directly to the condenser. The invention will be better understood and other details, features and advantages of the invention will become apparent on reading the following description given by way of nonlimiting example with reference to the appended drawing in which: FIG. 1 is a view schematic and partial, of a system according to an exemplary embodiment of the invention, - Figure 2 is a block diagram illustrating different modes of operation of the system of Figure 1, and - Figures 3 to 5 represent, schematically and partially FIG. 6 is a diagrammatic and partial sectional view of the machine 3 of the system of FIG. 1; FIGS. 7 and 8 show a system according to a another embodiment of the invention, in two operating situations.

FIG. 1 shows a system 1 for a motor vehicle, comprising: an equipment of the motor vehicle 2, an electric machine 3 configured to start an internal combustion engine 4 of the vehicle, this machine 3 being furthermore configured to operate mechanically the equipment 2.

The motor 4 comprises a rotary shaft 17, as can be seen in FIG. 3. This shaft is a crankshaft.

The machine 3 comprises a rotary shaft 18 integral with a rotor rotating within a stator.

The electric machine 3 is reversible so that, in addition to being able to start the combustion engine, it can operate as an alternator driven by the combustion engine 4. In other words, the electric machine 3 makes it possible to perform the Stop-Start function, making it possible to automatically restart the combustion engine at the end of an automatic shutdown phase.

This automatic stopping phase corresponds for example to a stop at a red light, and the combustion engine is restarted when the driver presses the accelerator pedal.

The machine may be a synchronous rotating electrical machine with double excitation, that is to say comprising a rotor provided with permanent magnets and an excitation winding. The invention is, in the example described, applied to a truck or a bus.

When the machine 3 operates as an alternator, this reversible machine produces electric current that charges a battery, not shown, of the vehicle.

The electric machine 3 has an electric power of between 4 and 25 KWatts, in particular a power substantially equal to 8 KWatts. This type of machine 3 is a machine driven belt.

The electric machine 3 is configured to generate electric current during braking of the vehicle engine. This allows regenerative braking.

The electric machine 3 is further configured to assist the combustion engine 4 when the latter is in operation. The machine 3 is, according to another name, an alternator-starter.

The machine 3 comprises a power electronics, an inverter, integrated.

In the example described, the equipment 2 is configured to be able to operate using the electric machine 3 when the combustion engine 4 is at a standstill. The equipment 2 is a mechanical air conditioning compressor of the vehicle.

The compressor 2 is used in a HVAC system of the motor vehicle.

The compressor 2 can be controlled in speed to compress or pressurize a refrigerant with one or more rotary pistons actuated by a rotary member 6 of the compressor 2, as can be seen in Figure 3 in particular. Other types of compressor can be used if desired. The rotary member 6 is a rotary shaft, this rotary member having an axis of rotation X1 offset with respect to the axis of rotation X2 of the electric machine 3, these axes X1 and X2 being parallel and separated by a non-zero distance . The rotary shaft 6 is operated for compressed air.

In the example described, the shaft 6 of the equipment 2 is configured to be able selectively: - to be decoupled in rotation from both the combustion engine 4 and the electric machine 3 so as to be at rest, - to be driven in rotation by the combustion engine 4, - be rotated by the electric machine 3. The rotary shaft 6 of the equipment 2 is associated with a drive member 8, a pulley, which is selectively coupled and decoupled screws with respect to the shaft 6, so that when the drive member 8 is coupled with the shaft 6, they rotate together, and when the drive member 8 is decoupled from the shaft 6, the drive member 8 can rotate without driving the shaft 6.

The pulley 8 of the equipment 2 is rotated systematically when the electric machine 3 rotates. The equipment 2 comprises an electromagnetic clutch 9 arranged to selectively couple and decouple the pulley 8 and the shaft 6 of the equipment, as can be seen in FIG.

The electric machine 3 comprises a first drive member 21 associated with the internal combustion engine 4 and a second drive member 22 associated with the equipment 2, the two members 21 and 22 being able to be selectively secured in rotation or disengaged in rotation . These members 21 and 22 are rotatable both around the axis of rotation X2.

The two drive members 21 and 22 are interconnected by an electromagnetic clutch 25 arranged to selectively couple and decouple the two drive members 21 and 22.

The driving members 21 and 22 each comprise a pulley.

The pulley 22 is integral with the shaft 18 of the machine 3.

The electric machine 3 and the combustion engine 4 are coupled by a first transmission belt 31, which is mounted on the pulley 21.

The electric machine 3 and the equipment 2 are coupled by a second transmission belt 32, which is mounted on the pulley 22 of the electric machine 3.

The first and second transmission belts 31 and 32 are distinct.

The combustion engine 4 comprises a drive member 35, a pulley, cooperating with the first transmission belt 31. This pulley 35 is integral with the shaft 17 of the engine 4, as illustrated in FIG.

Different modes of operation of the system 1 will now be described.

Depending on the activation of the air conditioning in the vehicle, illustrated by the control step 40 in Figure 2, different cases of operation occur.

When the control step 40 corresponds to a deactivation (OFF) of the conditioned air, namely the compressor 2 is at rest, the motor 4 and the machine 3 can operate without driving the compressor 2 (step 41 of FIG. 2) . This mode will be described in more detail with reference to FIG.

When the control 40 corresponds to an activation (ON) of the conditioned air, namely the compressor 2 is running, the motor 4 and the machine 3 can operate by mechanically driving the compressor 2. In one case (step 42), the combustion engine 4 is running, as better described with reference to Figure 3. In the other case (step 43), the internal combustion engine 4 is stopped, as described in more detail in Figure 4 .

In the operating mode corresponding to step 42, and with reference to FIG. 3, the system 1 operates as follows: the electromagnetic clutch 25 is closed so that the two drive members 21 and 22 are coupled in rotation. - The combustion engine 4 drives the two drive members 21 and 22 coupled, the drive member 22 of the electric machine 3 driving the compressor 2 via the pulley 8 of the compressor 2, the clutch 9 being closed. Thus, the electric machine 3 operates as an alternator and the compressor 2 is in operation.

In the operating mode corresponding to step 43, and with reference to FIG. 4, the system 1 operates in the following manner: the combustion engine 4 is at a standstill, for example in an automatic stopping phase - The electric machine 3 operates in motor mode, and the clutch 25 between the two drive members 21 and 22 of the machine is open, the two drive members 21 and 22 thus being uncoupled, - On the machine 3 , the drive member 22 drives the shaft 6 of the compressor 2 via the belt 32 and the clutch 9 is closed, and the uncoupled drive member 21 does not drive the combustion engine 4. Thus the compressor 2 is in operation while the combustion engine 4 is at a standstill.

In the operating mode corresponding to step 41, and with reference to FIG. 5, the system 1 operates as follows: the combustion engine 4 is in operation and drives the electric machine 3 which acts as an alternator; The clutch 25 on the electric machine is closed so that the pulley 21 in rotation drives the pulley 22 in rotation, these pulleys 21 and 22 being secured by the clutch 25, - The clutch 9 on the compressor 2 is open from so that the pulley 8 on the compressor 2 rotates without driving the rotary shaft 6 of the compressor. Thus the compressor 2 is stopped.

The system 1 comprises: - besides the electric machine 3, - a cooling circuit 50 of the machine arranged to cool the machine 3 and / or a power electronics, not shown, associated with this machine, this cooling circuit 50 being connected an air conditioning device 51, also called air conditioning device, of the vehicle. The power electronics may for example be an inverter associated with the machine 3.

It is possible to increase the electrical power of the electric machine 3 because this well cooled machine can produce more electrical power.

The air conditioning device 51 comprises in addition to the cooling circuit 50 of the electric machine, a ventilation circuit 52 arranged to selectively ventilate hot air or cold air in the passenger compartment.

The cooling circuit 50 of the electric machine and the ventilation circuit 52 of the passenger compartment are arranged to use the same compressor 2 of the air conditioning device 51.

The cooling circuit 50 of the machine and the ventilation circuit 52 are connected in series.

The air conditioning device 51 uses a heat transfer fluid capable of changing its state, in particular from a gaseous state to a liquid state and vice versa.

The air conditioning device 51 comprises a condenser 55 through which the heat transfer fluid can circulate, this condenser 55 being arranged to condense the heat transfer fluid from the gaseous state to the liquid state.

The air conditioning device 51 comprises an evaporator 56 through which the heat transfer fluid can circulate, this evaporator being arranged to evaporate the coolant from the liquid state to the gaseous state.

The air conditioning device 51 comprises an expansion valve 57 through which the heat transfer fluid can circulate, this expansion valve being arranged to expand the heat transfer fluid which is in the liquid state, the temperature of the heat transfer fluid then falling.

The air conditioning device is arranged to allow cooling of the coolant at a temperature below 10 ° C, especially below 5 ° C.

The cooling circuit 50 of the machine is arranged to cool the machine also when the machine operates as an alternator, this machine being then driven by the internal combustion engine of the vehicle.

The heat transfer fluid in the gaseous state after its exit from the machine 3 is compressed by the compressor 2, which increases the pressure and the temperature of the fluid.

While circulating between the compressor 2 and the condenser 55, the gas cools slightly in contact with the pipe between the compressor 2 and the condenser 55.

Then the heat transfer fluid passes successively through the condenser 55, the expansion valve 57 and the evaporator 56.

Then the heat transfer fluid in the gaseous state cools the machine 3 and this fluid is heated by the machine 3 by heat exchange.

As can be seen in Figure 6, the machine 3 comprises a casing 60 in which is housed a stator 61 of the machine 3. A rotor 62 is provided in known manner, rotating about the axis X2.

The casing 60 comprises a channel 65 for the passage of heat transfer fluid which allows the removal of calories from the machine 3, and particularly the stator 61.

This channel 65 may for example be annular, and extend around the stator 61.

This channel 65 is part of the cooling circuit 50 of the machine 3.

A separate channel of the housing may, alternatively, be provided. For example, such a channel can be made using a tube or several dedicated tubes.

In the example just described, the system only allows to cool.

FIGS. 7 and 8 show a system according to a variant of the invention, which allows the cabin to be selectively cooled and heated, depending on the requirements, for example as a function of the control of the driver of the vehicle.

The air conditioning device 51 comprises an inversion valve 70 fluidly connected to an outlet 71 of the compressor 2 so as to direct the heated fluid coming from the compressor selectively towards the condenser 55 or the ventilation circuit 52.

The ventilation circuit is arranged to ventilate in the passenger compartment the air heated by the heat transfer fluid via the evaporator 56, when the inversion valve 70 directs the heat transfer fluid from the compressor 2 directly to the ventilation circuit 52 without pass through the condenser 55, as is the case of Figure 8.

The ventilation circuit is arranged to ventilate cooled air in the passenger compartment via the evaporator 56, when the inversion valve 70 directs the heat transfer fluid from the compressor 2 directly to the condenser 55, as is the case with Figure 7.

In the operation of Figure 7, namely the cooling of the passenger compartment, the thermodynamic cycle is similar to that of Figure 1.

In the operation of FIG. 8, namely the heating of the passenger compartment, the inversion valve 70 makes it possible for the heat transfer fluid to perform a path opposite to that of FIG. 7.

In this case, the fluid first goes into the evaporator 56 and then through the expansion valve 57, then through the condenser 55 to get into the machine 3 to cool.

The expansion valve 57 is arranged to allow the fluid to expand as this fluid passes through the valve in one direction or another. For example, the expansion valve 57 may be formed by two expansion valve members each acting for a direction of fluid flow.

Claims (14)

1. System (1) for a motor vehicle, this system comprising: an electric machine (3) configured to provide torque to an internal combustion engine of the vehicle, in particular for starting the internal combustion engine (4) of the vehicle, a circuit cooling device (50) of the machine arranged to cool the machine and / or a power electronics associated with this machine, this cooling circuit being connected to an air conditioning device (51) of the vehicle so that the air conditioning device selectively supply hot air or cold air to the passenger compartment of the vehicle. 2. System according to the preceding claim, the electric machine (3) being reversible so that, in addition to being able to provide a torque to the combustion engine, be able to operate as an alternator driven by the combustion engine. 3. System according to one of the preceding claims, the electric machine (3) having an electrical power between 4 and 25 KWatts, especially between 6 and 12 KWatts, including a power substantially equal to 8 KWatts. 4. System according to one of the preceding claims, the machine is further configured to mechanically operate equipment formed by a compressor (2), including the air conditioning device. 5. System according to one of the preceding claims, the equipment (2) being configured to operate with the electric machine (3) when the combustion engine of the vehicle is stopped. 6. System according to the preceding claim, the rotary member (6) of the equipment being configured to selectively be able: - to be decoupled in rotation from both the combustion engine and the electric machine so as to be at rest, - to be rotated by the combustion engine, - being rotated by the electric machine. 7. System according to one of the preceding claims, the air conditioning device (51) comprises in addition to the cooling circuit of the electric machine, a ventilation circuit (52) arranged to selectively ventilate hot air or air cold in the cockpit. 8. System according to the preceding claim, the cooling circuit of the electric machine and the ventilation circuit of the passenger compartment are arranged to use the same compressor (2) of the air conditioning device. 9. System according to one of the preceding claims, the air conditioning device comprises a condenser (55) through which can circulate the heat transfer fluid, the condenser being arranged to condense the heat transfer fluid from the gaseous state to the liquid state. 10. System according to one of the preceding claims, the air conditioning device comprises an evaporator (56) through which the heat transfer fluid can circulate, this evaporator being arranged to evaporate the coolant from the liquid state to the gaseous state. 11. System according to one of the preceding claims, the air conditioning device comprises an expansion valve (57) through which can circulate the heat transfer fluid, the expansion valve being arranged to expand the heat transfer fluid which is at the liquid state, the temperature of the heat transfer fluid then falling. 12. Device according to one of the preceding claims, the air conditioning device (51) comprises an inversion valve (70) connected to an outlet (71) of the compressor (2) so as to direct the heated fluid from the compressor selectively to the condenser (55) or the ventilation circuit (52). 13. Device according to the preceding claim, the ventilation circuit is arranged to ventilate in the passenger compartment of the air heated by the coolant when the inversion valve (71) directs the heat transfer fluid from the compressor (2) directly to the ventilation circuit (52) without passing through the condenser (55). 14. Device according to one of the two preceding claims, the ventilation circuit is arranged to ventilate cooled air in the passenger compartment when the inversion valve (71) directs the heat transfer fluid from the compressor (2) directly to the condenser (55).