Scroll compressor with oil return for refrigerant-oil mixtures

Abstract

The present invention relates to a scroll compressor (1) with oil return for refrigerant-oil mixture, the scroll compressor (1) comprising a housing element (2) and a fixed scroll (3), wherein the housing element (2) is connected to the fixed scroll (3) by means of a seal (4) such that an outlet chamber (6) is formed between the housing element (2) and the fixed scroll (3), wherein, for oil separation and oil return purposes, an oil separation chamber (9) having a high-pressure refrigerant outlet (10) and an oil collection area (13) and an oil return passage (12) toward a suction pressure chamber (15) are arranged downstream of the outlet chamber (6), the scroll compressor being characterized in that an outlet chamber discharge member (11) for discharging oil into the oil return passage (12) of the oil separation chamber (9) is formed in the lower region of the outlet chamber (6) relative to the ground.

Description

Technical Field

[0001] This invention relates to a scroll compressor for a refrigerant compression system, in which a refrigerant-oil mixture is compressed. After compression, the refrigerant oil is separated and supplied in a short-loop manner to the areas of the mechanical compressor components to be lubricated, thereby effectively lubricating the compressor. Background Technology

[0002] Downstream of the compression chamber, a general-purpose refrigerant compressor has an outlet chamber into which the refrigerant-oil mixture is introduced under high pressure. The outlet chamber has only one outlet for the compressed mixture containing refrigerant oil, which leads directly to an oil separator. In the oil separator, the oil is separated and conveyed to the suction side upstream of the compressor unit via at least one pressure-reducing element through an oil return path. Because the specially designed oil separator is located downstream, the outlet chamber itself does not have any special structural elements that function as an oil separator. Therefore, there is no oil return path, etc. The outlet chamber is preferably designed as a cavity with the maximum possible volume, as the large volume provides damping for the discharge pressure pulse and thus provides improved NVH performance (noise, vibration, and harshness).

[0003] A known problem with existing scroll compressors is that the outlet chamber in the rear housing downstream of the compressor unit is not designed as an oil separator, because a larger volume chamber is typically preferred in this location to suppress discharge pressure pulsations. Because the volume of this chamber is larger compared to the outlet of a fixed scroll compressor, the flow velocity is significantly reduced. In particular, in the case of low mass flow, the reduction in flow velocity in the outlet chamber unintentionally acts as an oil separator due to the different mass inertia of oil and refrigerant.

[0004] Therefore, under low-quality flow conditions, the oil separated in the outlet chamber is no longer usable for the compressor. For example, only when running at high-speed, high-quality flow can this oil be transported out of the outlet chamber and reused for the compressor.

[0005] According to the prior art, JPA 2019-056322 discloses a refrigerant compressor having two continuously arranged oil separators and two separate oil return passages in order to overcome the aforementioned disadvantages of scroll compressors.

[0006] In the aforementioned document, structural elements for oil separation have been implemented in the outlet chamber to form an additional oil separator arranged upstream. Furthermore, the oil intentionally separated in the first upstream oil separator is directly conveyed to the compressor unit via a dedicated oil return channel, which also has dedicated nozzle elements. This oil return channel is additionally formed relative to a conventional oil return channel, which, according to the prior art, is supplied with oil separated in the oil separator. The oil return channel leads to separately positioned inlets for entering the suction chamber and the compressor chamber of the scroll compressor. Summary of the Invention

[0007] Technical issues

[0008] The purpose of this invention is to improve oil return in the compressor in order to ensure stable and reliable lubrication of the compressor when it is operating at a low mass flow rate.

[0009] This objective is achieved by a subject matter having the features of claim 1. Further developments are specified in the dependent claims.

[0010] Technical solution

[0011] The object of the present invention is achieved in particular by a scroll compressor with oil return for a refrigerant-oil mixture, which, in addition to other conventional components of a scroll compressor, includes a housing element and a fixed scroll attached to the housing element. The housing element is connected to the fixed scroll such that an outlet chamber for compressing the refrigerant-oil mixture is formed between the housing element and the fixed scroll, downstream of the pressure chamber, and such that the outlet chamber is defined by the housing element and the fixed scroll. To seal the outlet chamber as a space, a seal is arranged between the housing element and the fixed scroll. For oil separation and oil return purposes, an oil separation chamber is provided downstream of the outlet chamber, which, in part, has a high-pressure refrigerant outlet and an oil collection area. An oil return passage is arranged in the lower region of the oil collection area toward the suction pressure chamber of the scroll compressor. The pressure difference is balanced via nozzle elements, etc. The scroll compressor is characterized in that an outlet chamber discharge element for discharging oil into the oil separation chamber is formed in the lower region of the outlet chamber relative to the ground. Under low-mass flow conditions, the oil separated in the outlet chamber passes directly through the outlet chamber discharge section and enters the return oil passage along the shortest possible path, and then enters the suction pressure chamber to lubricate the moving parts of the scroll compressor.

[0012] Preferably, the outlet chamber valve is integrated into the outlet chamber of the scroll compressor and arranged and configured such that the compressor outlet, which is arranged in the fixed scroll and leads to the outlet chamber, can be controlled. Therefore, the outlet chamber valve controls the refrigerant-oil mass flow from the compressor outlet into the outlet chamber.

[0013] Particularly preferably, an outlet chamber passage is formed in the upper region of the outlet chamber relative to the ground for connection with an oil separation chamber for the refrigerant-oil mixture. After the compression process and after the flow through the outlet chamber, the refrigerant-oil mixture thus enters the oil separation chamber via the outlet chamber passage, where the intentional oil separation from the mixture takes place.

[0014] Advantageously, the oil separation chamber and the oil return channel are both integrated into the housing element, eliminating the need for additional components.

[0015] An advantageous embodiment of the invention includes a return oil passage formed at least partially through a fixed vortex toward the suction pressure chamber. In this embodiment, the transition of the return oil passage from the housing element to the fixed vortex is fluid-sealed by means of a seal.

[0016] Particularly preferably, the outlet chamber discharge element is also formed as a channel within the housing element.

[0017] The concept of the invention is extended when the channel is formed as a hole in the housing element. From a manufacturing point of view, this is a very simple and uncomplicated measure for realizing the channel.

[0018] Another advantageous embodiment of the channel includes forming it as a stepped orifice in the housing element, with a nozzle-shaped constriction formed upstream of the connection with the return oil channel. The nozzle-shaped constriction allows for particularly precise control of the fluid flow entering the return oil channel through the channel.

[0019] Particularly advantageously, individual nozzle elements are arranged in the channel, which are preferably interchangeable. Thus, for example, when changing the refrigerant oil, the nozzle elements can be adapted to different rheological properties of the oil.

[0020] As an alternative to the channel formation described above, the outlet chamber discharge element is formed as a groove in the sealing surface of the housing element.

[0021] As another alternative, the outlet chamber discharge element is formed as a groove in the sealing surface of a fixed vortex.

[0022] As another alternative, the outlet chamber discharge element is formed as a slit seal, so that the outlet chamber discharge element is formed through an orifice in the seal.

[0023] Another advantageous alternative implementation of the outlet chamber discharge element includes forming it as a channel in the sealing surface of the housing element.

[0024] The above-described embodiments are advantageously further improved if the channels in the sealing surface of the housing element are formed as a labyrinth or in a tortuous manner.

[0025] When formed as a hole or a circular channel, the outlet chamber discharge component preferably has a circular flow cross-section with a diameter of 1.2 mm at its narrowest point.

[0026] If the diameter of the outlet chamber discharge part is too large, this results in a significant increase in back pressure used to press the vortex.

[0027] This is consistent with the 1.131mm diameter of the outlet chamber discharge component at its narrowest point, such as the nozzle opening. 2 The flow cross section approximately corresponds to.

[0028] The concept of this invention includes providing a second inlet leading to the existing oil return channel, instead of a second return oil passage, to discharge a certain amount of oil that may be accidentally separated at the operating point from the outlet chamber. This second inlet is located downstream of the standard oil separator but upstream of the nozzle element of the return oil passage, and therefore at approximately the same pressure as the oil separated in the oil separation chamber, so that the compressor can regain the amount of oil accidentally separated in the outlet chamber based on the mass flow. The shape and cross-section of the other outputs of the outlet chamber discharge must be designed such that, on the one hand, oil can be discharged from the outlet chamber, and on the other hand, the compressor efficiency should not be reduced, and the back pressure system for pressing the movable scroll element, which may exist in the event of no oil or only a small amount of oil being separated, should not be altered at the operating point.

[0029] Therefore, the outlet from this chamber should be located near the bottom. In particular, the inlet of the standard oil return passage must be positioned so that no refrigerant mixes into the return oil at the operating point, where there is no separated oil in the chamber, as this would especially lead to a decrease in the viscosity of the oil-refrigerant mixture and thus an increase in back pressure.

[0030] The refrigerant-oil mixture reaches the outlet chamber downstream of the rear casing of the constant-scroll compressor outlet. After the outlet chamber, the refrigerant-oil mixture enters the oil separator. From the oil separator, the low-oil portion of the refrigerant-oil mixture exits the compressor via the high-pressure refrigerant outlet. The separated oil is transported to the suction side via the oil return passage.

[0031] This invention solves the aforementioned problems with minimal design effort and in a particularly easy-to-implement manner. Accidentally separated oil is discharged from the outlet chamber to the return oil passage via a second outlet and an outlet chamber discharge component. This improves oil management, which in particular leads to a reduction in the amount of oil required for air conditioning systems and thus improves the system's performance characteristics.

[0032] The improved pulsation characteristics under low-flow operation are also related to this concept. Particularly advantageous is the absence of any negative impact on efficiency or the potential back pressure on the rotating scroll of the electric compressor.

[0033] A particular advantage of the present invention is that arterial characteristics are improved under operating conditions with low quality flow or flow rate due to the reduction in the amount of oil accidentally separated.

[0034] To incorporate the unintentionally separated mass flow from the outlet chamber into the lubrication circuit, the separated oil is supplied back to the compressor through another inlet leading to the established return oil path. The shape and cross-section of the connection are advantageously designed so that any accidentally accumulated oil is discharged from the outlet chamber into the defined return oil path without altering efficiency and back pressure characteristics. Attached Figure Description

[0035] Further details, features, and advantages of embodiments of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings, in which:

[0036] Figure 1A: A portion of the scroll compressor is shown in longitudinal section.

[0037] Figure 1B: Details of the housing elements and the fixed vortex are shown in longitudinal section.

[0038] Figure 2A: Housing element shown in axial view

[0039] Figure 2B: Shows the cross-section AA of the housing element.

[0040] Figure 2C: Showing details of the nozzle element formed in a single piece.

[0041] Figure 2D: Showing details of the individually formed nozzle element.

[0042] Figure 2E: Details of the nozzle element formed as a stepped orifice.

[0043] Figure 2F: A cross-sectional view of a housing element with a seal.

[0044] Figure 3A: Axial view showing the fixed vortex and housing elements.

[0045] Figure 3B: Shows a cross-section of the housing element BB

[0046] Figure 3C: Shows details of the housing components.

[0047] Figure 3D: Shows the gap sector of the cross section DD of the housing element.

[0048] Figure 3E: Shows the gap length of the cross section DD of the housing element.

[0049] Figure 3F: Shows details of the housing components.

[0050] Figure 3G: Shows the gap sector of the seal of the housing element.

[0051] Figure 4A: Shows details of the housing element for the channel seal.

[0052] Figure 4B: Shows the cross-section FF of the housing element.

[0053] Figure 4C: A perspective view of a housing element with a seal.

[0054] Figure 4D: Shows a seal with a gap.

[0055] Figure 4E: Shows a seal with a groove.

[0056] Figure 4F: An enlarged view of a seal with grooves.

[0057] Figure 5A: A cross-sectional view of a housing element with channels.

[0058] Figure 5B: Shows the cross-section GG of the housing element.

[0059] Figure 5C: A cross-section of a housing element with a tortuous channel is shown. Detailed Implementation

[0060] Figure 1 shows a portion of a scroll compressor 1 in longitudinal section. In the schematic diagram, the scroll compressor 1 is shown as having a housing element 2 and a fixed scroll 3 connected to each other. Between the housing element 2 and the fixed scroll 3, sub-regions of surfaces that support each other are sealed in a fluid-tight manner by a seal 4. In the fixed scroll 3, a compressor outlet 5 is formed as a passage through which a compressed refrigerant-oil mixture flows under high pressure into an outlet chamber 6 formed between the fixed scroll 3 and the housing element 2. The outlet chamber 6 is formed as a cavity within the housing element 2, and one side of the outlet chamber 6 is defined by the rear of the fixed scroll 3. In its upper region, the outlet chamber 6 has an outlet chamber passage 8 leading to an oil separation chamber 9. The oil separation chamber 9 has a high-pressure refrigerant outlet 10 in its upper region and an oil collection area 13 in its lower region, the oil collection area 13 having a particulate filter optionally pressed into the oil collection area. The particulate filter is positioned such that the passage from the outlet chamber 6 remains upstream of the filter, so that oil must still pass through the filter when entering the return oil passage 12.

[0061] The oil return passage 12 extends from the oil collection area 13 toward the stationary scroll 3, wherein the oil return passage 12 is routed through the latter and finally terminates in the suction pressure chamber 15 or back pressure chamber 14 with a corresponding throttling element. In the above embodiment, the scroll compressor 1 corresponds to the prior art. The mass flow of the refrigerant-oil mixture in the scroll compressor 1 is routed in the following manner. After the mechanical compressor unit of the scroll compressor 1, the refrigerant-oil mixture is conveyed via the compressor outlet 5, also called the main outlet, in the stationary scroll 3 to the high-pressure area of ​​the rear housing, the outlet chamber 6. Due to the increase in the size of the flow cross-section from the compressor outlet 5 to the outlet chamber 6, the oil entering the outlet chamber 6 with the refrigerant-oil mixture separates from the refrigerant and is not further transported. For example, this occurs depending on the operating conditions of the scroll compressor 1 at lower speeds. At this location, some separation of oil from the refrigerant-oil mixture is unintentional, and only under operating conditions with relatively high volumetric flow rates is the oil unintentionally separated in the outlet chamber 6 picked up again by the refrigerant mass flow and transported away. Accordingly, the amount of oil in the current cycle depends on the operating conditions of the scroll compressor 1. The refrigerant-oil mixture leaves the outlet chamber 6 and heads towards the oil separation chamber 9, which is designed as a cyclone separator. In the oil separation chamber 9, the refrigerant and oil are separated due to their different densities. The refrigerant eventually leaves the scroll compressor 1 via the high-pressure refrigerant outlet 10. The oil separated in the oil separation chamber 9 accumulates in the oil collection area 13 and is transported to the suction pressure chamber 15 and the back pressure chamber 14 via the oil return passage 12.

[0062] According to the design of the scroll compressor 1, the back pressure for pressing the moving scroll is also regulated in the back pressure chamber 14 through the oil return channel 12, as shown in Figure 1.

[0063] The invention is characterized in that a second outlet is provided in the housing element 2 leading to the return oil passage 12. This is highlighted in the exemplary embodiment shown in FIG. 1A. The second outlet is formed as an outlet chamber discharge member 11 and connects the outlet chamber 6, and in particular the lower region of the outlet chamber 6 relative to the ground, to the return oil passage 12.

[0064] As described above, after the compressor unit, the refrigerant-oil mixture is conveyed via the compressor outlet 5 of the fixed scroll compressor 3 to the high-pressure area, outlet chamber 6, of the housing element 2. Due to the increased size of the flow cross-section, some oil in the refrigerant-oil mixture is not conveyed upwards through the refrigerant-oil mixture depending on the operating conditions in each case. This undesirable side effect occurs at the lower speeds of the scroll compressor 1. Therefore, a certain amount of oil in outlet chamber 6 depends on the operating conditions. Oil return is achieved by the mass flow of the refrigerant-oil mixture leaving outlet chamber 6 toward oil separation chamber 9, where the refrigerant and oil are separated. The oil-free refrigerant in the oil separation chamber, which still contains a small amount of oil, leaves the scroll compressor 1 via the high-pressure refrigerant outlet 10 of the scroll compressor. The oil intentionally separated from oil separation chamber 9 accumulates in the oil collection area 13 formed in the housing and is conveyed to the suction side of the scroll compressor 1 via the oil return channel 12. The back pressure for pressing the moving scroll compressor is also regulated through this channel, depending on the compressor design. Crucial for improving oil circulation is the additional inflow of oil from the outlet chamber 6 through the outlet chamber discharge member 11, as provided by the present invention. A small volumetric flow primarily consisting of oil exits the outlet chamber 6 at its bottom through the outlet chamber discharge member 11. This oil volumetric flow contains only a small fraction of the refrigerant dissolved therein and is added to the oil volumetric flow in the return oil passage 12. This occurs depending on operating conditions and is schematically illustrated by arrows in the lower region of the housing element 2.

[0065] In Figure 1B, the housing element 2 and the fixed scroll 3 housed by the housing element 2 are shown in a highly schematic manner as the basic components of the scroll compressor 1. The passage for receiving and directionally guiding the refrigerant-oil mixture is shown here at an enlarged scale.

[0066] The compressor outlet 5 in the fixed scroll 3 leads to the outlet chamber 6, the wall of which is formed partly by the housing element 2 and partly by the fixed scroll 3. A seal 4 is arranged between the fixed scroll 3 and the housing element 2 to seal the outlet chamber 6. In the upper region, the outlet chamber 6 is connected to an outlet chamber passage 8, which leads to an oil separation chamber 9. The oil separation chamber 9 has a high-pressure refrigerant outlet 10 in the upper region and an oil collection area 13 in the lower region. An oil return passage 12 begins in the oil collection area 13, through which the outlet chamber discharge element 11 extends from the outlet chamber 6.

[0067] Oil that has unintentionally separated in the outlet chamber 6 under certain operating conditions can therefore directly enter the return oil passage 12 via the outlet chamber discharge member 11, and oil circulation can be maintained under all operating conditions, especially even when only a relatively low volumetric flow rate is transmitted at a relatively low speed. The return oil passage 12 first extends in the housing element 2 to the stationary vortex 3 and continues to extend in the stationary vortex 3, in which a seal 4 is correspondingly arranged to seal the transition from the housing element 2 to the stationary vortex 3.

[0068] In the exemplary embodiment shown, an outlet chamber valve 7 is arranged in the outlet chamber 6, which controls the mass flow of the refrigerant-oil mixture from the compressor outlet 5.

[0069] Figures 2A, 2B, 2C, 2D, 2E and 2F show housing element 2, in which the outlet chamber discharge element is formed as channel 17.

[0070] Figure 2A shows an axial view of housing element 2 in cross-section, while Figure 2B shows the marked section AA.

[0071] Detail B from Figure 2B is finally shown in Figure 2C at an enlarged scale. According to this embodiment of the invention, the nozzle geometry of channel 17 is integrated into the material of housing element 2. Different shading lines are chosen to visualize the nozzle element, which is itself part of the base material. The variable nozzle thickness t corresponds to the flow length of the nozzle. The nozzle position can be arranged along the orifice axis in the region of orifice depth h of channel 17. The nozzle diameter d is again schematically shown in Figure 2C. N and hole diameter d B The arrangement of the nozzles and the diameter of the channel 17, as well as the diameter of the nozzles, are variable depending on the refrigerant, oil, and operating conditions.

[0072] It should be emphasized that a variable cross-section can also be formed along the nozzle thickness t.

[0073] Figure 2D shows a separate nozzle element 19 according to detail B of Figure 2B. The separate nozzle element 19 has a diameter d. N The nozzle can be reversible and interchangeable, and its external geometry and shape can differ from those shown. Advantageously, it can be oriented along the nozzle length l. N Forming a variable nozzle cross-section, l N It can vary depending on the nozzle geometry and the available material thickness. Nozzle length l N Throughout the entire thin nozzle diameter d of nozzle element 19 N The extension is shown in Figure 2D. The nozzle inlet d is also shown. B and nozzle outlet d TBThe variable orifice diameter. The position t of nozzle element 19 along orifice depth h. N It is variable. The nozzle element 19 can be fixed in the hole, for example, by various fastening methods, namely by form fit, material fit, or force fit. The position of the nozzle element 19 at the height h and the depth of the hole can be specified according to the type of form fit, material fit, or force fit connection.

[0074] In Figure 2E, the directly generated hole is formed as channel 17. Hole diameter d B and nozzle outlet d TB It can be varied accordingly. Hole depth t B and t TB It can also be adjusted based on the available space. TB With t B With d TB The variable ratio between them is possible, allowing, for example, flow resistance or mass flow to be adjusted. As a general requirement, d B Greater than d TB And preferably d B Much greater than d TB .

[0075] Therefore, channel 17 is designed as a stepped hole, which initially has a depth t at the hole depth. B The diameter d of the hole over the length B And then have in length t TB The nozzle outlet d TB The diameter.

[0076] The orifice serving as channel 17 can also be alternatively formed without cross-sectional shrinkage, i.e., having a nozzle outlet d. tb The diameter. Then, over the entire length t... B and t tb It has a constant hole diameter d B .

[0077] Figure 2F illustrates the positional range specifications for the aforementioned embodiments. A portion of the sealing surface 20 from the housing element 2 and the sealing region 24 between the fixed vortex 3 and the housing 2 is shown. All forms or variations can be positioned on the marked sealing surface 20. Furthermore, a fully filled region is shown, within which the individual channels 17 are formed. If necessary, a material deposit can be added if the available material thickness is insufficient. This additional material deposit must be able to connect to the high-pressure channels.

[0078] All the variations shown in Figures 2A to 2E can be performed perpendicularly, parallelly, or at an angle relative to the plane shown in Schematic 2F.

[0079] Figures 3A to 3G illustrate embodiments of the invention, wherein the sealing surface in the housing element 2 or the sealing surface in the fixed vortex 3 is interrupted, partially removed, for example, cut off or milled. The seal 4 shown in the figures is designed, for example, an O-ring, a molded rubber seal, and a coated or uncoated metal seal.

[0080] Figures 3A to 3D show the grooves in the sealing surface of the outer casing and housing element 2.

[0081] In Figure 3A, the fixed vortex 3 and the housing element 2 are shown in an axial view.

[0082] Figure 3B shows a longitudinal section BB through the relevant region of the scroll compressor 1.

[0083] In Figure 3C, detail C is now shown at an enlarged scale, and the groove depth t is shown. G And seal 4 and cross-section line DD.

[0084] Figure 3D finally shows the cross-section DD, where housing element 2 is removed and the return oil passage 12 is shown. The groove 22 has a tangential groove length L shown as a fan shape. R .

[0085] The groove 22 in housing element 2 establishes the connection between outlet chamber 6 and return oil passage 12. Seal 4 does not act on the width of groove 22. Groove depth t G The value and the tangential groove length l R or L R The value of is variable, and its purpose is to prevent large particles from passing through the cross-section of the resulting groove 22. Groove depth t G and the length of the tangential groove l R or L R The required flow restriction features are defined. If it can be connected to the return oil passage 12, the position of the groove 22 can be freely selected towards the fixed vortex 3 throughout the sealing area 24. The groove 22 can be produced by milling, as a pre-fabricated or forged feature, or by any other method.

[0086] A schematic diagram in Figure 3E has been added, showing the cross-section DD in a different embodiment. In this case, the embodiment is characterized by a slot formed in the housing sealing wall of the housing element 2 toward the fixed vortex 3. The groove depth t of the groove 22 G (Not shown) is variable and larger than the embodiment shown in Figure 3D. Variable tangential groove length l RThis is smaller compared to the embodiment shown in Figure 3D. Both sizes again define the desired flow-limiting features. If configured to connect to the return oil passage 12, the design of the groove 22 allows for free selection of the slot's position towards the fixed vortex 3 throughout the sealing area 24. The slot can again be produced by milling, as a pre-fabricated or forged feature, or by any other method.

[0087] Figure 3F shows details C of an outlet chamber 6, a housing element 2, a fixed vortex 3, a seal 4, and a groove 22, wherein, in this embodiment, the groove 22 is formed or made in the fixed vortex 3. A cross-section EE extending through the seal 4 is also shown. Here, the line defining the outlet chamber 6 is collinear with the sealing surface of the housing element 2.

[0088] Groove depth t G and the length of the tangential groove l R or L R It is variable. Two values ​​are selected to achieve the desired flow restriction characteristics. If connection with the return oil passage 12 can be achieved, the position of the groove 22 can be freely selected along the sealing line between the housing element 2 and the fixed vortex 3. The groove 22 can be produced by milling, as a prefabricated or forged feature, or by any other method. The shape of the groove 22 can differ from the illustration shown without departing from the concept of the invention.

[0089] Figure 3G shows the cross-section EE of seal 4, with groove length l. R It is formed in the fixed vortex 3 in the planar diagram.

[0090] Figures 4A and 4B illustrate other embodiments with applicable seal 4.

[0091] Figure 4A shows details C of a fixed vortex 3, a housing element 2, an outlet chamber 6 formed between the fixed vortex 3 and the housing element 2, and a return oil passage 12. A key feature is a cut-off seal 4, which is cut off between the outlet chamber 6 and the return oil passage 12, preventing oil from entering the return oil passage 12 from the outlet chamber 6. The seal 4 is ineffective at the cut-off point, instead allowing oil to pass through the seal 4 or through it intentionally and in a controlled manner.

[0092] The section line FF is shown in detail at a magnified scale in Figure 4B. Cutout 23 in seal 4, with a seal cutting depth t, is shown here. C Variable seal cutting depth t C It can also be produced by modifying the mold. A variable cut length along the sealing element ensures no large particles pass through the resulting cross-section. Two values ​​are selected to achieve the desired flow restriction characteristics. If set to connect to the return oil channel 12, this location can be freely selected along the entire seal line between the housing and the fixed vortex.

[0093] Figure 4C shows a perspective view of the housing element 2 with the oil return channel 12.

[0094] Figures 4D and 4E each show a portion of seal 4 through which oil can pass. Seal 4 can be designed as a sealing ring, a molded rubber portion, or a coated or uncoated metal strip seal. The depth and length of the passable portion of the seal are adjusted based on functional testing to achieve the desired characteristics. If it can be connected to the return oil channel 12 and / or the outlet channel, the passable portion of seal 4 can move freely along the sealing line.

[0095] Figure 4D shows a fully slotted seal 4 with a notch 23. The notch 23 is designed as a slot throughout the seal 4.

[0096] Figure 4E shows the design of seal 4, where the cutout 23 is not formed over the entire height of the sealing element, as opposed to Figure 4D. Figure 4F shows the area of ​​seal 4 with the cutout 23 at an enlarged scale. Here, seal 4 is cut out only over a portion of the height of the sealing element.

[0097] In Figures 5A, 5B and 5C, a channel 17 for conveying oil out of the outlet chamber 6 is formed on the sealing area 24 of the housing element 2.

[0098] Figure 5A shows the housing element 2 arranged within the outlet chamber 6. Channel 17 connects the outlet chamber 6 to the return oil channel 12. Channel 17 has a channel width b. C .

[0099] Figure 5B shows a cross section GG from Figure 5A, which schematically illustrates the channel depth t. C This corresponds to the previously exemplary implementation of the seal cutting depth.

[0100] To adjust flow characteristics, select a variable channel profile and / or channel width b. C and channel depth t C The length of channel 17 is adapted to the geometry of the high-pressure chamber. Channel 17 is manufactured, for example, during the process of casting, forging, or machining housing element 2. Channel 17 is also designed as a laminar flow throttling valve, for example, having a flat vortex shape or by means of a 3D vortex shape.

[0101] In Figure 5C, channel 17 is shown as a tortuous connection from outlet chamber 6 to return channel 12 in housing element 2. This embodiment of channel 17 will also be referred to as a labyrinth, which also includes the tortuous design of channel 17. For the embodiment of channel 17 in housing element 2 or as a labyrinth, an alternative embodiment is that channel 17 may also be provided by a separate component, such as a seal or a spiral nozzle. As shown in Figure 5C, the material required to form the labyrinth channel must be obtained within housing element 2. The labyrinth can be produced by prefabrication, forging, or machining. All characteristics, particularly the possibility of using it as a laminar flow throttling valve, also apply to this embodiment.

[0102] List of reference numerals

[0103] [Table 1]

[0104]

[0105]

[0106]

Claims

1. A scroll compressor (1) with oil return for a refrigerant-oil mixture, the scroll compressor (1) comprising: The housing element (2) and the fixed vortex (3) are connected to the fixed vortex (3) by means of a seal (4), such that an outlet chamber (6) is formed between the housing element (2) and the fixed vortex (3). For oil separation and return purposes, an oil separation chamber (9) having a high-pressure refrigerant outlet (10) and an oil collection area (13) and an oil return passage (12) toward the suction pressure chamber (15) are arranged downstream of the outlet chamber (6). The outlet chamber is characterized in that an outlet chamber discharge member (11) for discharging oil into the oil return passage (12) of the oil separation chamber (9) is formed in the lower region of the outlet chamber (6) relative to the ground, wherein the outlet chamber discharge member (11) is directly connected to the oil return passage (12) of the oil separation chamber (9), and wherein the outlet chamber discharge member (11) is formed as a seal (4) with a cut (23).

2. The scroll compressor (1) according to claim 1, characterized in that, An outlet chamber valve (7) is arranged and formed in the outlet chamber (6) so that the compressor outlet (5) arranged in the fixed scroll (3) can be controlled.

3. The scroll compressor (1) according to claim 1, characterized in that, An outlet chamber passage (8) for connecting to the oil separation chamber (9) for the refrigerant-oil mixture is formed in the upper region of the outlet chamber (6) relative to the ground.

4. The scroll compressor (1) according to claim 1, characterized in that, The oil separation chamber (9) and the oil return channel (12) are integrated in the housing element (2).

5. The scroll compressor (1) according to claim 1, characterized in that, The return oil passage (12) is formed to be at least partially through the fixed vortex (3) toward the suction pressure chamber (15).

6. The scroll compressor (1) according to claim 1, characterized in that, The outlet chamber discharge component (11) has a circular flow cross section with a diameter of 1.2 mm at its narrowest point.

7. The scroll compressor (1) according to claim 1, characterized in that, The outlet chamber discharge component (11) has a width of 1.131 mm at its narrowest point. 2 The flow cross section.

Images