ASSEMBLY COMPRISING A GENERATOR AND ELECTRIC MOTORS, FOR A VEHICLE AIR-CONDITIONING OR REFRIGERATION SYSTEM

Abstract

An assembly, having a generator and electric motors, for a vehicle air-conditioning or cooling system, having: a compressor intended to be driven by a heat engine, a top-up electric motor for driving the compressor when the latter is not or cannot be driven by the heat engine, a generator with permanent magnets having a shaft which can be driven in rotation by the heat engine, the generator and the top-up electric motor being disposed on this shaft, one or more condenser and/or evaporator electric motors of a vehicle air-conditioning or cooling system, said electric motors being configured to be powered by a direct current, the generator powering the electric motor or motors through a converter configured to supply a direct current, notably a low-voltage controller.

Claims

1. An assembly comprising a generator and electric motors, for a vehicle air-conditioning or cooling system, comprising: a compressor intended to be driven by a heat engine, a top-up electric motor for driving the compressor when the latter is not or cannot be driven by the heat engine, a generator with permanent magnets having a shaft which can be driven in rotation by the heat engine, the generator and the top-up electric motor being disposed on this shaft, one or more electric motors of condensers and/or of evaporators a vehicle air-conditioning or cooling system, said electric motors configured to be powered by a direct current, the generator powering the electric motor or motors a converter configured to supply a direct current, notably a low-voltage controller.

2. The assembly as claimed in claim 1, the power supply voltage of the electric motor or motors of condensers and/or of evaporators the output voltage of the converter, notably a low voltage, for example a direct voltage of 48 V.

3. The assembly as claimed in claim 1, the input voltage of the converter being a low voltage, for example a voltage of 33 V.

4. The assembly as claimed in claim 1, wherein the generator is synchronous.

5. The assembly as claimed in claim 1, the top-up electric motor comprising a squirrel cage rotor.

6. The assembly as claimed in claim 1, the shaft comprising a serration.

7. The assembly as claimed in claim 1, the heat engine and the electric motor or motors to a vehicle cooling or air-conditioning system.

8. The assembly as claimed in claim 1, wherein the generator and the top-up electric motor are contained in a common housing.

9. The assembly as claimed in claim 1, comprising a rocker switch device for powering the top-up electric motor, making it possible to supply the latter from the electrical network, the rocker switch device being able to notably comprise one or more switches for that purpose.

10. The assembly as claimed in claim 9, the rocker switch device being configured so that, when the heat engine is stopped, the condenser and/or evaporator electric motors powered by the generator, and the compressor is driven by the top-up electric motor.

11. The assembly as claimed in claim 1, wherein the compressor has a mechanical drive, notably with pistons.

12. The assembly as claimed in claim 1, wherein the top-up electric motor comprises an eight-pole rotor.

13. The assembly as claimed in claim 12, wherein the electric motor or motors are each used to drive a fan.

14. A method for operating an assembly as claimed in claim 1, wherein either (i) the compressor and the generator are driven by the heat engine, notably when a vehicle bearing the assembly is on the road, the generator then being able to supply electricity to the electric motors of the condensers and/or evaporators, notably through a converter configured to supply a direct current, notably a low-voltage controller, or (ii) the compressor is driven by the top-up electric motor, notably when a vehicle bearing the assembly is stopped, the condenser and evaporator motors then being able to be powered by the generator, the generator being also driven by the top-up electric motor.

Description

[0057] The invention will be able to be better understood on reading the following detailed description of a nonlimiting exemplary implementation thereof, and on studying the attached drawing, in which:

[0058] FIGS. 1a to 1c are perspective views of an electricity production device of an assembly, embedded or not, produced in accordance with the invention,

[0059] FIG. 2 schematically represents this assembly,

[0060] FIG. 3 is a schematic view, in longitudinal cross-section, of the device of FIGS. 1a to 1c,

[0061] FIGS. 4 and 5 are schematic views, in transverse cross-section, respectively of the top-up electric motor and of the generator,

[0062] FIG. 6 is a side view of the shaft of the generator and of the top-up electric motor,

[0063] FIGS. 7a and 7b are detail views, in transverse cross-section, of the shaft of FIG. 6, respectively along A-A and B-B,

[0064] FIG. 8a is a schematic and partial perspective view of the serration tool which can be used, and

[0065] FIG. 8b is a view thereof in transverse cross-section.

[0066] FIGS. 1a to 1c and 2 show an assembly 1 comprising, on the one hand, a heat engine 3, and, on the other hand, an electricity production device 2 having a generator 4 whose shaft 25 can be driven in rotation by the heat engine 3.

[0067] The assembly 1 is, for example, embedded on a vehicle. In the example described, the heat engine 3 is a diesel engine.

[0068] The assembly also comprises electric motors 8, 9 of an air-conditioning or cooling system of the vehicle or of the trailer of the vehicle, powered by the electricity production device 2. In the example described, the assembly comprises a condenser motor 8 and two evaporator motors 9. Their number could of course be different without parting from the scope of the present invention. There could notably be two condenser motors and two evaporator motors.

[0069] These electric motors 8, 9 are configured to be powered by a direct voltage, 48 V DC in the example described.

[0070] The electricity production device 2 is configured so that the generator powers the electric motors through a converter 10 configured to supply a direct current, notably a low-voltage controller.

[0071] The power supply voltage of the electric motors is the output voltage of the converter 10. The input voltage of the converter can be a low voltage, for example a voltage of 33 V. The input voltage of the converter is the output voltage of the generator 4.

[0072] The assembly comprises a compressor 15 driven by the heat engine 3 via a coupling 6. The driving can be done by pulley and belt. The assembly thus has no electrically-driven compressor.

[0073] The assembly also comprises a top-up electric motor 16 for driving the compressor 15 when the latter is not or cannot be driven by the heat engine. The driving can be done by pulley and belt.

[0074] The top-up electric motor 16 is disposed on the same shaft 25 as the generator, so that the top-up electric motor and the generator can be contained in a common housing, or not. In the exemplary embodiment described, the assembly comprises two housings, one for the generator and one for the top-up electric motor. The housing or housings can be air-cooled or water-cooled.

[0075] The top-up electric motor 16 can be powered from the electrical network 11. Despite the presence of the top-up electric motor 16, the assembly has no electrically-driven compressor when the assembly is in on-road operating mode.

[0076] In the variant embodiment illustrated in FIG. 1, the generator 4 is driven by the heat engine 3 via a mechanical link involving the coupling 6, the compressor 15 and the shaft 25.

[0077] In the example described, the assembly also comprises a rocker switch device for powering the top-up electric motor, comprising switches 13 making it possible to power the top-up electric motor from the electrical network 11.

[0078] When the heat engine is stopped, the condenser and/or evaporator electric motors are powered by the generator, and the compressor is driven by the top-up electric motor. In this case, the generator is driven by the top-up electric motor. Thus, the top-up electric motor powers both the compressor and the generator which powers the electric motor or motors.

[0079] As can be seen in FIG. 3, the device 2 comprises a single end of shaft 25. Furthermore, the generator comprises a flange 22 making it possible to dismantle a rolling bearing 23 disposed at the front of the generator. The device 2 is, in the example described, of IP55 class.

[0080] Moreover, the heat engine 3 drives the shaft 25 of the generator 4 by pulley and belt, which allows the output frequency of the generator to be adjusted to the speed of the heat engine. The heat engine 3 can drive the generator 4 at a variable speed. For example, when the charge of the generator is low, the speed of rotation of the heat engine 3 is relatively low, and when the charge of the generator 3 increases, the speed of the heat engine 3 can be increased.

[0081] FIGS. 3 and 4 illustrate an exemplary embodiment in which the top-up electric motor 16 comprises a rotor formed by a stack of magnetic plates comprising notches 17. The notches receive aluminum injected under pressure, thus forming bars linked to one another at the end of the stack of plates by short-circuit rings. The aluminum can be replaced by copper, notably in order to reduce the electrical resistivity of the bars, in order to improve the efficiency and/or the magnetic power gain.

[0082] FIGS. 3 and 5 illustrate an exemplary embodiment in which the generator 4 comprises a stator with distributed winding. In the example described, it comprises a rotor 19 with permanent magnets 18 buried under the surface of the poles 20, as illustrated in FIG. 5. The magnets can be of ferrite or rare earth (for example NeFeB) type. The rotor illustrated comprises four poles 20, but could comprise 6 or 8 thereof. In another variant that is not illustrated, the magnets could be disposed on the surface.

[0083] The permanent magnets 18 are held by end rings 21 disposed on each side of the rotor mass. These rings can be made of aluminum.

[0084] This generator for example has a power of 3.6 kW at an operating speed of 1800 rpm.

[0085] The shaft 25 is represented on its own in FIG. 6. In the example described, it comprises a part 25a bearing serrations 26, as illustrated in FIGS. 7a and 7b. This part is intended to receive the generator and/or the top-up electric motor.

[0086] The serration is created by striking the shaft by means of a serration tool, and more particularly two serration tools, one lower and the other upper. A serration tool 30 comprises two chisels 31 defining the length of the serration on the shaft 25, as illustrated in FIGS. 8a and 8b.