Device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle

Abstract

Device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle, said device comprising a compressor (2) of said fluid and an electric machine (4), said device further comprising a housing (6) receiving said machine (4), said housing (6) being configured so that said fluid passes through said machine (4) for cooling said machine (4), said machine (4) comprising a shaft (26) for driving the compressor (2) around a longitudinal axis (X), said longitudinal axis (X) being intended to be horizontal under normal conditions of use, said device comprising a member (28), integral in rotation with the shaft (26), for agitating the fluid in the housing (8). Figure for the abstract: Figure 1

Description

Title of the invention: Device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle

[0001] The invention relates to a device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle,

[0002] In this field, compression devices are known comprising a fluid compressor and an electrical machine. Said machine comprises a compressor drive shaft. These devices are configured so that the fluid passes through the machine in order to cool the latter before entering the compressor.

[0003] The fluid comprises a portion intended for lubrication of the moving parts of the circuit through which it passes. In the compression device, the fluid is likely to stagnate and there is then a risk that the portion intended for lubrication separates from the rest of the fluid and is no longer entrained in the circuit.

[0004] The invention aims to at least partially overcome the above drawbacks and to this end proposes a device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle, said device comprising a compressor of said fluid and an electrical machine, said device further comprising a housing accommodating said machine, said housing being configured so that said fluid passes through said machine for the purpose of cooling said machine, said machine comprising a drive shaft of the compressor around a longitudinal axis, said longitudinal axis being intended to be horizontal under normal conditions of use, said device comprising a member, integral in rotation with the shaft, for agitating the fluid in the housing.

[0005] Thanks to the member for stirring the fluid, the device according to the invention allows mixing of the fluid in the area where it is likely to stagnate, namely the housing of the electrical machine, which allows it to be homogenized and vaporized to then be evacuated from the housing.

[0006] Preferably, said member for stirring the fluid extends radially outwards so as to stir a portion of said fluid likely to accumulate in the lower part of said machine.

[0007] Preferably again, said device comprises a mass, said device being configured so that said mass allows balancing of the drive of the shaft, said mass comprising said member for agitating the fluid. Thus, a single member, namely the mass, enables both balancing of said device and agitation of the fluid. In this regard, it may be noted that the combination of the fluid agitation function and the balancing function is particularly suitable in that the shape or shapes chosen to effect the agitation will necessarily contribute to the balancing, and all the more so as their radial extent will be large.

[0008] According to different additional features of the invention, which may be taken together or separately and which constitute so many embodiments of the invention: - said member for agitating the fluid has a distal end facing a clearance near an inner wall of said housing, - said blade is oriented substantially radially from said body, - said blade has a substantially constant cross section, - said mass comprises a balancing body and said member for agitating the fluid, in particular said fluid agitating blade, - said body is substantially flat, - said body is substantially orthogonal to said axis of rotation, - said body has a shape according to an angular portion of a ring, - said blade extends from said body, - said blade extends from an external peripheral edge of said angular portion, - said blade extends from a median zone of said body, according to an angular extension of said body, - said blade extends from a midpoint of said outer edge, - said blade has an angle of inclination with said body such that, along said longitudinal axis, said blade moves away from a plane of extension of said body from a proximal edge towards a distal edge of the blade, - said machine comprises a rotor for driving said shaft, - said member for agitating the fluid, in particular said blade, is directly or indirectly attached to the rotor, - said member for agitating the fluid, in particular said blade, is attached directly or indirectly to a lateral face of said rotor, - said balancing mass is attached to said rotor, - said compressor is a scroll compressor, - said electric machine comprises an electric motor and a control system for said motor, - said device is configured so that said fluid passes through said engine for the purpose of cooling said engine and said cooling system. order, - said housing comprises a partition separating a first and a second compartment of said housing, - said engine is housed in said first compartment, - said control system is housed in said second compartment, - said machine is configured so that said fluid is in contact with said partition, - said first compartment is located between said compressor and said second compartment along said longitudinal axis, - said member for agitating the fluid and / or said mass are located opposite said compressor.

[0009] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the detailed explanatory description which follows, of at least one embodiment of the invention given by way of purely illustrative and non-limiting example, with reference to the appended schematic drawings among which:

[0010] [Fig-1] schematically illustrates along a longitudinal section plane a example of a device in accordance with the invention;

[0011] [Fig.2] schematically illustrates in perspective a rotor of an electric machine of the device of [Fig.l].

[0012] It should first be noted that the terms upstream and downstream used in the following description refer to the direction of circulation of the fluid in question. Furthermore, the terms “first”, “second”, “third”, etc. are only used to distinguish the components concerned from each other and do not indicate an order or a possible importance of said components.

[0013] As illustrated in [Fig.l], the invention relates to a device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle. Said fluid comprises, for example, a refrigerant fluid and a lubricating fluid. Said refrigerant fluid is formed, in particular, of a hydrofluorocarbon, such as that known as R-134a. Alternatively, it is, in particular, the fluid known as R1234yf or carbon dioxide, also known as R744.

[0014] Said device comprises a compressor 2 of said fluid and an electrical machine 4. Said device further comprises a housing 6 accommodating said electrical machine 4, or even said compressor 2. Said housing 6 extends along a longitudinal axis X, intended to be horizontal under normal conditions of use.

[0015] In the illustrated embodiment, said electric machine 4 comprises an electric motor 8 and a system 10 for controlling said motor 8. Said electric machine 4, in particular said motor 8, comprises a shaft 26 for driving the compressor 2 around the longitudinal axis X.

[0016] Said electrical machine 4, in particular said motor 8, comprises a stator 60 and / or a rotor 62. The rotor 62 drives said shaft 26 in rotation. Said rotor 62 is here internal and the stator 60 is external. The shaft 26 is connected to the rotor 62 without any degree of freedom. Said shaft 26 and said rotor 62 are concentric. Said shaft 26 passes inside the rotor 62 along the longitudinal axis X.

[0017] Said housing 6 is configured so that said fluid passes through said electrical machine 4 for the purpose of cooling said electrical machine 4. More specifically, here, said device is configured so that said fluid passes through said motor 8 for the purpose of cooling said motor 8 while also allowing cooling of said control system 10.

[0018] Said housing 6 here comprises a partition 12 separating a first and a second compartment 14a, 14b of said housing 6. Said motor 8 is housed in said first compartment 14a. Said control system 10 is housed in said second compartment 14b. Said electrical machine 4 is configured so that said fluid is in contact with said partition 12, in particular before passing through said motor 8. In this way, by heat exchange through said partition 12, said fluid cools said control system 10. To promote such an exchange, said control system 10 is preferably fixed on said partition 12 and / or in heat exchange relationship with said partition 12.

[0019] Said first compartment 14a is located, for example, between said compressor 2 and said second compartment 14b along said longitudinal axis X. Said housing 6 here defines a housing 16 forming said first compartment and contiguously accommodating said compressor 2. Said device comprises, for example, a first cover 18 closing said housing 16 by being attached to said housing 6. Said device here comprises a second cover 20 closing said second compartment 14b by being attached to said housing 6. Said housing 6 is, for example, of cylindrical configuration.

[0020] Said compressor 2 is, for example, a spiral compressor. It comprises a fixed part 40 and a moving part 42. Said parts 40, 42 each define a spiral housing. Said moving part 42 and said fixed part 40 cooperate with each other so that their spiral housing mutually define successive pockets between at least one inlet 44 and one outlet 46 of said compressor 2. Said moving part 42 is rotated by said shaft 26 so that the fluid passes from one pocket to the other while being progressively compressed.

[0021] Said compressor 2 here has several suction orifices 44 for the fluid, preferably two suction orifices, located at a periphery of the compressor 2, and / or an outlet orifice 46, for example located in a fixed central part of the compressor 2. Said suction orifices 44 allow the fluid to penetrate between the fixed and moving parts 40, 42 to be progressively compressed while being driven towards the central part of the compressor 2 from where it exits through said outlet orifice 46.

[0022] For this, said moving part 42 has an axis of rotation X' offset radially relative to the longitudinal axis X. Said axis of rotation X' of the moving part 42 thus rotates around said axis of rotation X of the shaft 26. Said moving part 42 is further mounted according to a pivot connection on said shaft 26 so as to be free to rotate around its own axis of rotation X'. Said device further comprises an intermediate part 48, mounted freely to rotate around the shaft 26, to guide the moving part 42, according to the desired movement, in the fixed part 40. Given the asymmetries provided by the moving part 42, such a movement generates an unbalance phenomenon likely to cause vibrations.

[0023] To limit this phenomenon, said device advantageously comprises a mass 34, said device being configured so that said mass 34 allows balancing of the drive of the shaft 26. Such a mass 34 in particular allows balancing of the rotation of the shaft 26 during the rotation of the moving part 42 of the compressor 2. This will be mentioned again later in relation to a particular aspect of the invention.

[0024] Said device has an inlet 22 of said fluid in said housing 16, in particular located at said casing 6, and / or an outlet 24 of said fluid, in particular located at said first cover 18. The fluid thus enters the housing 16 through said inlet 22, at low pressure, axially passes through said motor 8 then said compressor 2 into which it enters through the suction ports 44 and exits through the outlet port 46 to exit, at high pressure, through said outlet 24.

[0025] According to the invention, said device comprises a member 28, integral in rotation with the shaft 26, for agitating the fluid in the housing 6. Said member 28 for agitating the fluid thus makes it possible to homogenize it in an area, namely the housing 6, in which said fluid is precisely likely to stagnate.

[0026] Advantageously, said member 28 for stirring the fluid extends radially outwards so as to stir a portion of said fluid likely to accumulate in the lower part of said machine. In the figures, the shaft 26 is in an angular position where the member 28 for stirring the fluid passes to the bottom of the housing 6, precisely in the area in question. Said member 28 for stirring the fluid advantageously has a distal end 29 coming opposite at a clearance close to an internal wall 30 of said housing 6 for the most complete stirring possible.

[0027] As is more visible in [Fig.2], said member 28 for agitating the fluid comprises, for example, a blade 32 for agitating the fluid. It has a straight portion 32a, parallel to said longitudinal axis X, extended by an inclined portion 32b, forming an angle with respect to a plane orthogonal to said longitudinal axis X. More generally, said blade 32 is oriented according to an essentially radial component. Here, it has a substantially constant cross section giving it the shape of a rod or finger.

[0028] The shape of the blade 32 described above is particularly advantageous since the simplicity of its configuration, in particular weight, shape and / or orientation, allows it to limit the risks of in turn generating an unbalance phenomenon. It is also easy to manufacture.

[0029] Preferably, said mass 34 comprises said member 28 for agitating the fluid. Thus, according to this aspect of the invention, the same member, namely the mass 34, makes it possible both to balance said device and to agitate the fluid. Said member 28 for agitating the fluid and the rest of the mass are configured so that, taken in combination, they present the desired unbalance compensation function.

[0030] Said mass 34 advantageously comprises a balancing body 52 and said fluid stirring blade 32.

[0031] Said body 52 is, for example, substantially planar and / or orthogonal to said axis of rotation X. Said body 52 here has a shape according to an angular portion of a ring, in particular a half-ring shape extending angularly over 180°. Said body 52 has a thickness depending on the unbalance to be compensated.

[0032] Said blade 32 extends from said body 52. ​​More precisely, here, said blade 32 extends from an external peripheral edge 54 of said angular portion and, even more precisely, from a median zone of said body 52, according to an angular extension of said body 52. ​​In other words, said blade 32 extends from a midpoint of said external edge 54.

[0033] Said blade 32 advantageously has an angle of inclination with said body 52 so that, along said longitudinal axis, said blade 32 moves away from a plane of extension of said body from a proximal end 56 towards the distal end 29 of the blade 32.

[0034] Said member 28 for agitating the fluid is integral, directly or indirectly, with the rotor 62. It can thus be configured more easily than if it came from the shaft 26 because the rotor 62 has a larger diameter than said shaft 26. Said member 28 for agitating is advantageously attached, directly or indirectly, to a lateral face 64 of said rotor 62.

[0035] In the illustrated embodiment, said balancing mass 34 is attached to said rotor 62, in particular said lateral face 64, by plane-to-plane contact. Said balancing mass 34 is, for example, riveted to said lateral face 64.

[0036] If we refer again to [Fig.l], we see that said member 28 for agitating the fluid and / or said mass 34 are located opposite said compressor 2. They are therefore on the side of the motor 8 opposite that located in a bottom of the housing 16.

[0037] Said device is configured so that said blade 32 rotates opposite the stator 60. More specifically, here, said device is configured so that said blade 32 rotates in an annular cavity defined internally by a lateral flank 70 of said intermediate part 48, externally by said internal wall 30 of the housing 70 and laterally, on the one hand, by the stator 60 and on the other hand, by a transverse wall 72 of said intermediate part 48.

Claims

Claims

1. Device for compressing a fluid, in particular for a heating, ventilation and / or air conditioning system, in particular of a motor vehicle, said device comprising a compressor (2) of said fluid and an electric machine (4), said device further comprising a housing (6) receiving said machine (4), said housing (6) being configured so that said fluid passes through said machine (4) for cooling said machine (4), said machine (4) comprising a shaft (26) for driving the compressor (2) around a longitudinal axis (X), said longitudinal axis (X) being intended to be horizontal under normal conditions of use, said device comprising a member (28), integral in rotation with the shaft (26), for agitating the fluid in the housing (8).

2. Device according to the preceding claim in which said member (28) for agitating the fluid extends radially outwards so as to stir a portion of said fluid likely to accumulate in the lower part of said machine (4).

3. Device according to any one of the preceding claims in which said member (28) for agitating the fluid advantageously has a distal end (29) coming opposite, with a clearance, an internal wall (30) of said housing (6).

4. Device according to any one of the preceding claims in which said member (28) for agitating the fluid comprises a blade (32) having a substantially constant cross section.

5. A device according to any preceding claim wherein said device comprises a mass (34), said device being configured so that said mass (34) allows balancing of the drive of the shaft (26), said mass (34) comprising said member (28) for agitating the fluid

6. Device according to the preceding claim in which said mass (34) comprises a balancing body (52) and said member (28) for agitating the fluid.

7. Device according to the preceding claim in which said body (52) is substantially planar and / or substantially orthogonal to said axis of rotation (X).

8. Device according to any one of claims 6 or 7 in which said body (52) has a shape according to an angular portion of a ring.

9. Device according to any one of claims 5 to 8 wherein said machine (4) comprises a rotor (62) for driving said shaft (26), said balancing mass (34) being attached to said rotor (62).

10. Device according to any one of claims 5 to 9 in which said mass (34) is located opposite said compressor (2).

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