COMPRESSOR HAS SPIRAL TEAM Of a DEFLECTOR Compared to the OPENING Of ASPIRATIONMENAGE IN ITS ENVELOPE

The present invention relates to a scroll compressor with a deflector facing the vacuum orifice formed in its envelope.

A scroll compressor includes a sealed housing including a suction chamber having an entrance port for the gas and a discharge chamber or pressure chamber. The suction and discharge chambers are separated by a partition wall. A pump arranged to the rise in pressure of the suction gas consists of two scrolls: a fixed scroll connected in one piece with the partition and a movable scroll driven by the shaft of an electric motor in the suction chamber, the movable scroll being offset from the shaft to execute an orbital motion with the fixed scroll and define pockets of variable volumes and increasingly low during rotation of the shaft. The gas is thus compressed in the pockets before escaping toward the discharge chamber.

Because of the working clearances between the fixed and movable scroll defining the pockets into which the gas is compressed, it is necessary that the gas admitted in the pockets is slightly loaded by oil to the oil seal facilitates the inter-pockets, to provide a satisfactory compression during operation of the compressor.

Therefore, it would be desirable that the gas taken in the suction chamber can be loaded in oil homogeneously, and sufficiently, to optimize this sealing.

It is known, in particular by the document US 5,055 010 equip a scroll compressor of a baffle disposed within the suction chamber, opposite the gas inlet therein. Such a deflector is intended to distribute the flow of gas to the two inputs of the compression stage, by increasing the energy performance of the compressor by allowing the direct passage of a portion of the gas to the compression stage.

However, such an arrangement does not allow the problem of loading the gas oil particles, homogeneously, at the two entries in the compression stage. Indeed, if the portion of the gas stream which is deflected by the deflector towards the bottom of the compressor performs therein a substantial path in the suction chamber, for loading oil, the portion of the flow which is deflected directly towards the compression stage is not charging oil, or very little, in the case that there is a suction effect between the deflector and the inlet of the compression stage located above the baffle.

The aim of the invention is to provide a scroll compressor provided with a deflector facing the gas inlet aperture in the suction chamber, which can be set approximately homogeneously oil particles in the gas to be supplied to the different suction ports of the compressor stage.

To this end, the device that it relates to, of the type comprising a cylindrical casing sealed, a suction chamber disposed within the shell, a scroll mechanism disposed within the housing, means for generating a lubricant mist, a suction inlet gas opening radially into the suction chamber, and a baffle disposed opposite the suction inlet and cooperating with the casing to define a channel having at least an upper opening feeding suction gas to the scroll mechanism, is characterized in that the upper opening is shaped to deflect the gas in a region of the suction chamber wherein is generated, in operation, an oil mist by the generator means of the mist.

Advantageously, the generator means of the oil mist are constituted by a counterweight integral with the drive shaft in its area located inside the suction chamber.

The portion of the gas stream directed by the deflector towards the compression stage, does not flow directly to the compression stage, but is returned to the interior of the suction chamber where the gas is charged with oil particles.

In an embodiment of the device, the end of the deflector located on the side facing the compression stage comprises a right-L divert the flow of gases of 180°.

Advantageously, the end of the return in L is located in substantially the same plane as the upper edge of the channel formed by the deflector.

This arrangement thus creates a baffle effect.

In one embodiment of the device according to the invention, the deflector is constituted by a cross-section with the general shape of Ω, whose wings are used to fasten on the inner face of the envelope substantially parallel to the axis of the compressor and of which the body defines the channel for supplying a gas to the suction chamber.

In one possibility, the channel delimited by the deflector can also be delimited by a recess in the inner face of the casing of the compressor.

Preferably, the channel has an upper opening and a lower opening and comprises two parts, that turned toward the compression stage is smaller in cross section than facing the engine.

In order to achieve proper flow rate distribution, the gas inlet opens into the channel portion of the larger section facing the motor, the section-reducing zone providing the transition between the two parts of the channel being offset from the side of the compression stage relative to the inlet opening.

According to one embodiment of the device, in its region of small section turned towards the compression stage, the deflector has a flat central surface, while, in the region of large section turned towards the motor, the deflector has a central surface in the shape of a segment of cylindrical surface.

According to another feature of the invention, the length of the deflector is such that the latter extends on either side of the inlet aperture to a distance at least equal to the diameter of the inlet port.

In any case, the invention will be clearly understood with the aid of the description that follows, with reference to the appended schematic drawing representing, by way of non-limiting example, one embodiment of a scroll compressor equipped with this suction device:

Figure 1 is a longitudinal sectional view of the compressor;

Figure 2 is a perspective view, partially torn off, a deflector constituting the compressor according to the present invention, in the mounted position on the interior of the envelope of a compressor;

Figure 3 is a view in longitudinal section of the deflector of the line III-III of Figure 2;

Figures 4 and 5 are two views in cross-section respectively along the lines IV-IV and V-V figure 2.

The compressor shown in Figure 1 includes a sealed housing 2 within which are formed a suction chamber 3 provided with an inlet 4 for the gas and a discharge chamber or pressure chamber 5 provided with an outlet 6 for the gas. The suction chambers 3 and outlet 5 are separated by a partition wall 7. Within the suction chamber 3 is mounted an electric motor, the stator 8 and the rotor 9 are schematized to the pattern. The rotor 9 is associated with a shaft 10 passing through a body 11 of the compressor and guided in rotation in a lower bearing 12 and at least one upper bearing 13. The pump arranged to the rise in pressure of the suction gas consists of two scrolls, a fixed scroll 14 connected in one piece with the partition 7 and a movable scroll 15 driven by the motor shaft 10 and eccentric with relation to said shaft to describe an orbital movement and delimit with the fixed scroll, during rotation of the shaft, pockets of variable volume and lower and lower, in which the gas is compressed before escaping through an orifice 16 towards the discharge chamber 5. A valve system, designated by the general reference 17, is mounted onto the outlet 16, to allow the passage of the gas to the pressure chamber 5 and prevent flow of gas of the same chamber 5 to the suction chamber 3 when the compressor stops. In the bottom of the compressor there is a layer of oil 21, plunges into a pump 19 integral with the shaft 10, and for supplying via a pipe 20 internal to the shaft the bearings in which is guided the shaft 10, to effect lubrication thereof. The oil supply from the conduit 20 to the bearings is carried out via control slits 22. The oil used for lubricating the bearings and spring in emulsified form nebulized and is projected, under the action of an upper counterweight 10a secured to the shaft 10, within the enclosure constituting the suction chamber 3, due to the presence of a plurality of apertures in the body 11.

The compressor is equipped, opposite the gas inlet port 4, a deflector 18. The deflector 18 has a section shaped as Ω, comprising two longitudinal flanges 23 for attachment to the inside face of the shell 2, parallel to the axis of the compressor. The wings 23 are connected, in a portion of the deflector, by a curved central surface 24 in the shape of a segment of cylindrical surface, and in another portion of the deflector by a planar surface 26. These two surfaces are connected by an inclined zone 25. The deflector 18 delimits with the shroud a channel including a first portion facing the compression stage, and delimited by the flat surface 26 and a second portion, turned towards the motor, and delimited by the curved central surface 24. The second portion is larger in section than the first, providing a preferential passage of the fluid in a direction toward the engine. As shown the drawing, the gas inlet 4 within the shell opens into the channel portion of the larger section, the inclined zone 25 connecting the sections being offset from the side of the compression stage relative to the inlet opening.

The deflector 18 is equipped, at its end 27 on the side of the compression stage, in a return 28 L divert the flow of gases of 180°. The end 29 of the return 28 is located, as shown the drawing, substantially in the same plane as the upper edge of the channel formed by the deflector 18. Sizing of the return 28 is such that the passage cross section of the gas remains substantially constant, the output section at the edge 29 being substantially equal to the passage cross-section between the flat central surface 26 and the compressor shell.

Since the gas flow is deflected 180° at the exit part of the deflector, it returns in the center of the suction chamber 3, wherein loading it with oil particles. For its part, the gas which is deflected downwardly by the deflector 18 into the lower part of the suction chamber 3, where it also in oil particles. Therefore, the gas supplied to the two suction openings of the suction stage has about the same oil feed, sufficient to provide a seal homogeneous compression pockets, at the working clearances existing between the fixed part and the movable part of the compression stage.

As apparent from the foregoing, the present invention provides a great improvement to the existing art by providing a device of simple structure for providing uniform distribution of oil particles into the gas fed to the different suction ports of the compressor stage.

Since it is a matter of course, the invention is not limited to the single embodiment of the device, described above example, on the contrary it embraces all variants. Thus in particular that the shape of the upper portion of the deflector could be different, the deflector that could include a constant section over its whole length, that the deflector could be made of several parts, or that the deflector could be a fingerprint or recess in the outer face of the body of the compressor, without as much to the scope of the invention.