EP3212890A1

EP3212890A1 - Compressor, notably for motor vehicles

Info

Publication number: EP3212890A1
Application number: EP15794307.7A
Authority: EP
Inventors: Augustin Bellet; Hironobu Deguchi
Original assignee: Valeo Japan Co Ltd
Current assignee: Valeo Japan Co Ltd
Priority date: 2014-10-30
Filing date: 2015-10-28
Publication date: 2017-09-06
Also published as: CN107076144A; JP6697450B2; JP2017532495A; CN107076144B; WO2016067206A1; FR3027972B1; FR3027972A1

Abstract

The application concerns a compressor comprising a fixed part and a part (10) movable relative to said fixed part, aid movable part (10) being configured to follow an orbital movement around an orbit axis, said compressor further comprising at least one anti-rotation assembly (20), formed of a ring (22) and a pin (24) configured to immobilize said movable part (10) against rotation on itself during its orbital movement, said fixed part and said movable part (10) being separated at least locally by a space forming an axial clearance (J), crossed by said pin (24), said ring (22) penetrating into said space.

Description

Compressor, notably for motor vehicles

The technical field of the present invention is that of compressors, in particular air conditioning compressors, notably for motor vehicles.

In compressors known at this time there exist different types of compression mechanism. In one particular type, known as the "scroll" type, a movable scroll orbits relative to a fixed scroll. Such orbital movement makes it possible to compress and to impart movement to a refrigerant in an air conditioning circuit in order to condition an enclosure, for example a motor vehicle passenger compartment, thermally.

To ensure correct operation of such a mechanism, the rotation of the movable scroll on itself must be limited. It is known to use for this a plurality of rings connected to the part carrying the movable scroll. They are circumferentially distributed at its periphery. Each ring is associated with a pin connected to a fixed part of the compressor. The pin is locally in contact with the interior of the ring and remains free to move relative to the latter. As a result, the pin does not constitute an obstacle to the orbital movement of the movable scroll but prevents it from turning on itself.

This being the case, such a solution generates friction that it is necessary to limit. In the known solutions, there nevertheless exists a risk of incorrect positioning of the rings that can lead to numerous disadvantages.

An object of the present invention is therefore to facilitate correct positioning of the rings and there is therefore proposed a compressor comprising a fixed part and a part movable relative to said fixed part, said movable part being configured to follow an orbital movement around an orbit axis, said compressor further comprising at least one anti-rotation assembly formed of a ring and a pin, configured to immobilize said movable part against rotation on itself during its orbital movement, said fixed part and said movable part being separated at least locally by a space forming an axial clearance, crossed by said pin, said ring being flush with and/or penetrating into said space.

Extending the ring in this way prevents incorrect positioning thereof. This therefore prevents increasing the unwanted friction between the fixed parts and 5 the movable parts. This consequently limits the risks of premature wear that can lead to breakdowns. The noise generated by the compressor and excess power consumption are also limited.

The invention also concerns the following features, taken together or 10 separately:

- the compressor comprises a recess receiving said ring,

- said ring is oriented along said orbit axis in said recess,

- said ring is mounted in said recess with a radial clearance,

- said recess is cup-shaped, otherwise referred to as substantially U-shaped, i s - said ring bears against a bottom of said cup,

- said cup has a lateral wall of height h and the ring has an axial length greater than or equal to said height h;

- said recess is defined in said movable part;

- said ring is situated at a distance from said fixed part by a residual 20 clearance;

- the residual clearance is configured to prevent a flow of fluid from said recess into said space when said recess is entirely facing said fixed part;

- the fixed part is configured to allow ventilation of the fluid in said recess intermittently;

25 - said ring has a circular internal surface and/or a circular external surface,

- said pin has a circular cross section,

- said cup is tangentially flanked by an edge of greater thickness relative to a surface onto which said recess opens,

- said extra-thick edge is configured to slide on said fixed part,

30 - said compressor comprises a scroll compression mechanism,

- said compressor comprises a counterweight,

- said compressor comprises a clutch mechanism making it possible, if necessary, to provide a leak between said compressor body and said movable part or conversely to position said orbital scroll ideally relative to the fixed scroll so as always to close the compression pockets,

- said compressor comprises a drive shaft forming said orbit axis,

- said compressor comprises an electric motor for driving said movable part, in other words, said compressor is of electric type,

- said compressor comprises power electronics for controlling it.

Other features, details and advantages of the invention will emerge more clearly from a reading of the description given hereinafter by way of example and with reference to drawings in which:

- figure 1 is a view in longitudinal section showing one example of a compressor in accordance with the invention,

- figures 2a, 2b and 2c show diagrammatically the anti-rotation principle in the compressor from figure 1 ,

- figure 3 is a view in longitudinal section of a part of one example of a typical compressor showing this anti-rotation assembly,

- figure 4 is an enlarged and simplified view of the part of the compressor from figure 3 containing said anti-rotation assembly,

- figure 5 repeats figure 4 in a prior art configuration, the ring of the anti- rotation assembly in question being positioned incorrectly.

The invention concerns a compressor 1 shown in figure 1 , intended in particular to circulate and to pressurize a refrigerant circulating in an air conditioning circuit, notably for thermal conditioning in the passenger compartment of a motor vehicle.

Said compressor 1 comprises a fixed part 2 and a part 10 movable relative to said fixed part 2, said movable part 10 being configured to follow an orbital movement around an orbit rotation shaft 4.

To be more precise, said compressor here comprises a body or housing forming said fixed part 2 through which passes a rotation shaft 3. The latter turns about a principal axis of the compressor, forming said orbit shaft 4. This compressor shaft can be driven by a drive mechanism and the latter can take the form of a pulley in the case of a mechanical driven compressor. Such a drive mechanism is preferably an electric motor integrated into the compressor 1 . Said compressor could comprise a power supply and/or control unit 5 for said motor.

The shaft 3 is retained in rotation relative to the housing 2 and comprises at its end a drive stud 6. The latter is threaded into an eccentric bush 7. The eccentric bush 7 is in contact with a bearing 9 allowing rotation of the eccentric bush 7 relative to the movable part 10, which here is an integral part of a compression mechanism 1 1 of said compressor 1 . The drive stud 6 extends along an axis that is offset relative to the orbit shaft 4. Such a structure drives the eccentric bush 7 with an orbital movement about the orbit shaft 4, which is reflected in orbital movement of the movable part 10. Said compression mechanism is advantageously a scroll mechanism. In other words, it comprises a compression body 12 provided with a scroll 13 fixed relative to the housing 2 and a scroll 14 movable relative to the housing 2, carried by said movable part 10 and otherwise referred to as the orbital scroll. The orbital movement of the movable scroll 14 in the fixed scroll 13 makes it possible to compress and to drive the refrigerant that circulates in the air conditioning loop including such a compressor.

The eccentric bush 7 could comprise a counterweight 8. Such a weight is offset relative to the orbit shaft 4 and then makes it possible to balance the centrifugal forces generated by the orbital movement of the movable scroll 14.

This therefore balances forces and masses between these two elements.

Said compressor could advantageously comprise a clutch mechanism, not visible, making it possible to provide a leak between said compression body 12 and said movable part 10, notably achieved by articulation of the eccentric bush 7 around the drive stud 6.

As shown in figures 2a to 2c, said compressor further comprises at least one anti-rotation assembly 20, here six assemblies 20 regularly and circumferentially distributed around the orbit shaft 4. Each assembly is formed of a ring 22 and a pin 24, configured to immobilize said movable part against rotation on itself during its orbital movement about the orbit shaft 4. The ring 22 or each ring 22 advantageously has a circular internal surface 22a and/or a circular external surface 22b. It preferably forms a torus of substantially rectangular section. The pin 24 or each pin 24 advantageously has a circular cross section. When it occurs, contact between the ring and the pin is therefore substantially linear. In figure 2a, the orbital scroll 14 is situated at the upper side relative to the fixed scroll 13. The two scrolls then form an inlet chamber 26a, a compression chamber 26b and an outlet chamber 26c. The orbital scroll in this instance is immobilized against rotation by the contact of the pin 24 with the ring 22 of the anti-rotation assembly located at 60° in the clockwise direction from the upper anti- rotation assembly 20.

In figure 2b, the orbital scroll 14 is situated at the left side relative to the fixed scroll 13. There are seen the starting of closing of the inlet chamber 26a, a movement of the compression chamber 26b toward the central part and a reduction of the volume of the outlet chamber 26c making it possible to complete the compression and/or to start the draining of said outlet chamber. The orbital scroll is then immobilized against rotation by the contact of the pin 24 with the ring 22 of the upper anti-rotation assembly. In figure 2c, the orbital scroll 14 is situated at the lower side relative to the fixed scroll 13. The closure of the inlet chamber 26a is completed, the movement of the compression chamber 26b toward the central part continues and the volume of the outlet chamber 26c tends towards zero to drain said outlet chamber. The orbital scroll is then immobilized against rotation by the contact of the pin 24 with the ring 22 of the anti-rotation assembly located at 60° in the anticlockwise direction from the upper anti-rotation assembly.

It is also seen in the various figures that, for each anti-rotation assembly, the relative position of the pin 24 in the corresponding ring 22 is variable, or free, so that the anti-rotation assemblies leave the movable part 10 free to orbit around the orbit shaft 4 at the same time as immobilizing the movable part 10 against rotation on itself thanks to at least one of said anti-rotation assemblies 20.

As seen better in figures 3 and 4, here said compressor further comprises a force receiving plate 16 placed between said housing 2 and said compression body 12. Said force receiving plate, otherwise referred to as a seal in the rest of the application, is fixed relative to the housing 2. Said movable part 10 is advantageously in contact with said force receiving plate 16 at the level of a rib 17 of the movable part. Here said rib 17 is formed by an annular increase in the thickness of the material situated at the periphery of said movable part 10 on a surface 18 opposite the orbital scroll 14. Said rib 17 on said movable part 10 slides on said force receiving plate 16 during its orbital movement. Said force receiving plate 16 has a central opening 19 to allow the movement of the eccentric bush 7 and flow of fluid therethrough.

Said fixed part, here the housing 2, to be more precise said seal 16, and said movable part 10 are separated at least locally by a space forming an axial clearance J crossed by said pins 24 in order for the latter to be able to interact with the corresponding rings 22. For example, said space is defined between the surface 18 of said movable part 10 opposite the orbital scroll 14 and said seal 16. In other words, it corresponds here to the thickness of the rib 17, i.e. the dimension of the rib 17 along the orbit shaft 4.

In accordance with the invention, said ring 22 is flush with or even penetrates into said space forming the axial clearance J. This limits the risk of incorrect positioning of the ring 22, as described in more detail hereinafter. In other words, the depth of the recesses 30 is always less than the height of the rings 22.

Said compressor advantageously comprises a recess 30 receiving each of said rings 22. Here it therefore comprises six recesses 30 each corresponding to one of the rings 22. Said recesses 30 are preferably situated in the movable member 10, said pins 24 then being part of the fixed part, here the housing 2, and passing through orifices in said force receiving plate 16. For example, said pins 24 are formed by pins fitted into a bore situated in the housing 2. Said rings 22 are then situated at a distance from said fixed part, here said force receiving plate 16, with a residual clearance J'.

The residual clearance J' is equal to or preferably less than the axial clearance J.

In this regard, said force receiving plate 16 is advantageously configured so that, at each angular position of the movable part 10 around the orbit shaft 4, some of the recesses 30 are entirely in front of said force receiving plate 16 while others are at least partly facing its central opening 19. In the case of the recesses 30 entirely facing said seal 16, said residual clearance J' can then be configured to limit a flow of fluid, in particular a lubricant fluid mixed with the lubricating oil of the compressor, from said recesses 30 into said space forming the axial clearance J. In other words, as shown in figures 2, said force receiving plate 16, is advantageously configured so that, at each angular position of the movable member 10 about the axis of orbit 4, some of the recesses 30 are at least partially facing its central opening 19 while others are entirely in front of said force receiving plate 16. The recesses 30 which are partially facing the central opening 19 are allowed to introduce fluid flow, in particular a fluid mixed with compressor lubricating oil outside of said recess 30, into the recess 30. To the contrary, in the other recesses 30 which are entirely in front of said force receiving plate 16, the residual clearance J' may then be configured to restrict fluid flow. The intermittent restriction of fluid flow makes possible to hold and ventilate the fluid mixed with lubricant in the recesses 30, thus improving lubrication in the recesses 30, more precisely, lubrication between the pin and the ring. In other words, the central opening 19 is arranged so that each of the recesses 30 is intermittently released from the restriction of fluid flow by partially facing the central opening 19. Said rings 22 are oriented along said orbit shaft 4 in said recesses 30. They could be mounted with a radial clearance in said recesses 30. Said recesses 30 are cup-shaped, for example, opening onto the surface 18 of said movable part 10 opposite the orbital scroll 14. Here said cups are tangentially flanked by said rib 17.

Said rings 22 bear against an abutment 32 of said cups, which may be flat. The latter cups have a lateral wall 34 of height h and the rings 22 have an axial length greater than or equal to said height h. Said rings 22 therefore project from the surface 18 of said movable part 10 opposite the orbital scroll 14 by an amount corresponding to the difference between their axial length and the height h of said cups.

The effect of the invention will be clear from figure 5, corresponding to the configuration encountered in the prior art. In such a configuration, the axial length of the rings 122 is less than or equal to the height h of the recesses 130 in which they are situated. It is then found that the risk of angular offsetting by the angle a and therefore of incorrect positioning of said rings in said recesses 130 is then higher by virtue of the available space.

Claims

1. A compressor (1 ) comprising a fixed part and a part (10) movable relative to said fixed part, said movable part (10) being configured to follow an orbital movement around an orbit axis (4), said compressor further comprising at least one anti-rotation assembly (20), configured to immobilize said movable part (10) against rotation on itself during its orbital movement, said anti-rotation assembly (20) comprising a ring and a pin (24), said fixed part and said movable part (10) being separated at least locally by a space forming an axial clearance (J), crossed by said pin (24), said ring (22) being flush with and/or penetrating into said space.

2. The compressor as claimed in claim 1 comprising a recess (30) receiving said ring (22).

3. The compressor as claimed in the preceding claim wherein said ring (22) is oriented along said orbit axis (4) in said recess (30).

4. The compressor as claimed in either one of claims 2 or 3 wherein said ring (22) is mounted in said recess (30) with a radial clearance.

5. The compressor as claimed in any one of claims 2 to 4 wherein said recess (30) is cup-shaped.

6. The compressor as claimed in the preceding claim wherein said ring (22) bears against an abutment (32) of said cup.

7. The compressor as claimed in either one of claims 5 or 6 wherein said cup has a lateral wall (34) of height h and the ring (22) has an axial length greater than or equal to said height h.

8. The compressor as claimed in any one of claims 2 to 7 wherein said recess (30) is defined in said movable part (10) and said ring (22) is situated at a distance from said fixed part by a residual clearance (J').

9. The compressor as claimed in the preceding claim wherein the residual clearance (J') is configured to limit a flow of fluid from said recess (30) into said space when said housing is entirely facing said fixed part.

10. The compressor as claimed in claim 9, wherein each of said recesses (30) is released from the restriction of fluid flow when the recess (30) is not completely facing said fixed part (2).

1 1 . The compressor as claimed in any one of the preceding claims comprising an electric motor for driving said movable part (10).

12. The compressor as claimed in any one of the preceding claims comprising an electric motor and power electronics for controlling it.