CN111089059A

CN111089059A - Scroll compressor oil return device

Info

Publication number: CN111089059A
Application number: CN202010037870.1A
Authority: CN
Inventors: 黄志刚; 牟英涛; 李奇
Original assignee: Shanghai Highly New Energy Technology Co Ltd
Current assignee: Shanghai Highly New Energy Technology Co Ltd
Priority date: 2020-01-14
Filing date: 2020-01-14
Publication date: 2020-05-01

Abstract

The invention provides an oil return device of a scroll compressor, which comprises: the fixed scroll is provided with a first channel arranged along the axial direction of the scroll compressor, a second channel arranged along the axial direction of the scroll compressor on the upper bracket, and a third channel arranged along the axial direction of the scroll compressor on the stator; the capillary tube is provided with a first through groove along the axial direction of the scroll compressor; at least one of the first channel, the second channel and the third channel is provided with a capillary tube; the first channel, the second channel and the third channel are communicated to form an oil return channel; the oil return channel is communicated with an oil pool of the exhaust cavity and an oil pool at the bottom of the scroll compressor; according to the oil return management device, the through holes are formed in the side walls of the motor stator, the fixed scroll and the upper support and serve as oil return channels, oil return management is achieved, an oil return pipe is not required to be arranged independently, simplification of the structure and reduction of cost are achieved, and effective control of throttling is achieved.

Description

Oil return device of scroll compressor

Technical Field

The invention relates to the technical field of compressors, in particular to an oil return device of a scroll compressor.

Background

At present, scroll compressors are widely used in the automotive field due to their high performance and high reliability. Particularly, the development and the use of new energy automobiles have no need for scroll compressor products. Oil supply management and oil return management of a scroll compressor directly affect the reliability of the scroll compressor, and are one of the core technologies of the scroll compressor.

Chinese patent application No. 201510755767.X discloses an oil return control system for a scroll compressor, which introduces an oil return pipe to guide the lubricating oil on the back of a movable scroll back to an oil pool at the bottom of the compressor and avoid contacting with the discharged high-pressure gas; although this patent can realize the oil return management, the newly-increased oil return pipe not only increases part cost, and in the in-service use, often because the oil return pipe brings the noise problem with motor stator or casing contact.

Chinese patent application No. 201480042755.6 discloses a scroll compressor in which high-pressure lubricating oil in an exhaust chamber is led back to a main bearing chamber between an upper bracket and a movable scroll by forming oil return passages in side walls of a fixed scroll and the upper bracket. Meanwhile, the patent also realizes high-pressure throttling by adding the threaded rod piece in the oil return channel. However, this patent only introduces the lubricant into the chamber in which the main bearing is located. Most of lubricating oil enters the compressor cavity after the main bearing and the eccentric bearing are lubricated; part of the lubricating oil will leak to the low pressure chamber where the motor is located and enter the high pressure chamber along with the low pressure gas.

This presents two problems: first, most of the lubricant circulates among the main bearing cavity, the compressor cavity, and the discharge cavity. Due to the limited space of the main bearing chamber, if the rotating speed is increased, the lubricating oil which participates in circulation is increased, so that the chamber cannot bear, and the oil return management is ineffective. Secondly, although the amount of lubricating oil leaking into the low-pressure chamber is small, the lubricating oil is in an uncontrolled state, and the whole oil return management and control effect is also deteriorated. In addition, although the throttling is realized by inserting a rod piece with an external thread into the oil return passage, the throttling area can be controlled, when the external thread rod is installed, impurities such as aluminum scraps are generated due to scraping on the side wall of the installation hole. Further, this causes a problem of reliability of the compressor.

Disclosure of Invention

In view of the above, the present invention provides an oil return device for a scroll compressor, in which through holes are respectively axially formed in side walls of a fixed scroll, an upper bracket and a motor stator, and communicated to form an oil return passage, and a capillary tube with a through hole is disposed in the oil return passage, so that cost of oil return management is reduced, and effective throttling is achieved.

According to one aspect of the invention, an oil return device of a scroll compressor is provided, the scroll compressor comprises an upper cylinder cover, an upper bracket, a fixed scroll, a movable scroll and a motor, wherein an exhaust cavity is formed between the upper cylinder cover and the fixed scroll, and the motor comprises a stator; the device comprises:

a first channel which is arranged on the fixed scroll along the axial direction of the scroll compressor,

a second channel which is arranged on the upper bracket along the axial direction of the scroll compressor,

a third channel is arranged on the stator along the axial direction of the scroll compressor; and

the capillary tube is provided with a first through groove along the axial direction of the scroll compressor;

at least one of the first channel, the second channel and the third channel is provided with the capillary; the first channel, the second channel and the third channel are communicated to form an oil return channel; the oil return passage is communicated with the oil pool of the exhaust cavity and the oil pool of the scroll compressor.

Preferably, the cross sections of the first channel, the second channel and the third channel are all circular, the cross section of the first channel is a section of the first channel perpendicular to the length extension direction of the first channel, and the cross sections of the first channel, the second channel and the third channel are parallel.

Preferably, the capillary is an integrally formed cylindrical piece with an annular cross section, the cross section of the first through groove is circular, the outer diameter of the capillary is equal to the inner diameters of the first channel, the second channel and the third channel, and the cross section of the capillary and the cross section of the first through groove are parallel to the cross section of the first channel.

Preferably, the capillary tube is formed by encircling two cylindrical rods with semicircular cross sections, the cross sections of the cylindrical rods are provided with semicircular grooves, the grooves in the two cylindrical rods are encircled to form the first through groove, and the cross sections of the cylindrical rods are parallel to the cross section of the first channel.

Preferably, the first through groove is formed by inwards recessing from the outer surface of the capillary, the cross section of the first through groove is arc-shaped, and the cross section of the first through groove is parallel to the cross section of the first channel.

Preferably, the first channel and the second channel are connected in a sealing mode through an O-shaped sealing ring.

Preferably, the capillary has three, respectively a first capillary, a second capillary and a third capillary; the cross sections of the first through grooves in the first capillary tube, the second capillary tube and the third capillary tube are all circular, and the cross section of each first through groove is a section, perpendicular to the length extending direction, of the corresponding first through groove.

Preferably, the diameters of the first through grooves in the first, second and third capillaries are equal.

Preferably, the inner diameter intervals of the first channel, the second channel and the third channel are all 2mm to 4 mm.

Preferably, the cross section of the first through groove is circular, the range of the diameter of the first through groove is 0.3mm to 0.6mm, and the cross section of the first through groove is the cross section of the first through groove perpendicular to the length extension direction of the first through groove.

Compared with the prior art, the invention has the beneficial effects that:

according to the oil return device of the scroll compressor, the passages are respectively formed in the side walls of the fixed scroll, the upper bracket and the motor stator along the axial direction and are communicated to form the oil return passage, so that the lubricating oil in the exhaust cavity is guided back to the oil pool at the bottom of the scroll compressor, effective oil return management is realized, an oil return pipe is avoided being additionally arranged, the production cost of the compressor is reduced, and the structure is simplified;

the capillary tube with the through groove with the smaller inner diameter is arranged in the oil return channel, so that effective throttling and pressure maintaining of the high-pressure cavity are realized, and the condition that the refrigerating and heating efficiency of the air conditioner is influenced because lubricating oil enters the pipeline of the air conditioning system along with compressed gas can be avoided; and the problem of lubrication and oil shortage of the compressor caused by a large amount of consumption of the engine oil in the low-pressure cavity is avoided, and the working reliability of the compressor is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a partial longitudinal cross sectional view of a scroll compressor in an embodiment of the present invention showing the oil return apparatus of the scroll compressor disclosed in the present embodiment;

FIG. 2 is a schematic cross-sectional view of a capillary tube in the oil return device of the scroll compressor disclosed in the present embodiment;

FIG. 3 is a schematic structural view of a cylindrical rod constituting the capillary of FIG. 2, the cross-section of which is in a semi-annular configuration;

FIG. 4 is a schematic cross-sectional view of another embodiment of a disclosed capillary tube;

fig. 5 is a schematic perspective view of the capillary tube of fig. 4.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the subject matter of the present disclosure can be practiced without one or more of the specific details, or with other methods, materials, devices, etc. In other instances, well-known technical solutions have not been shown or described in detail to avoid obscuring aspects of the present disclosure. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

The terms "a," "an," "the," "said," and "at least one" are used to indicate the presence of one or more elements/components/parts/etc.; the terms "comprising," "having," and "providing" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.

As shown in fig. 1, the present invention discloses an oil return device for a scroll compressor, the scroll compressor includes an upper cylinder cover 101, an upper bracket 102, a fixed scroll 103, a movable scroll 104 and a motor, an exhaust cavity is formed between the upper cylinder cover 101 and the fixed scroll 103, and the motor includes a stator 105. An oil sump 109 is provided in the exhaust chamber. The fixed scroll 103 and the orbiting scroll 104 cooperate with each other to form a low pressure chamber, a medium pressure chamber, and a high pressure chamber, the medium pressure chamber being located between the low pressure chamber and the high pressure chamber. A suction cavity is formed between the fixed scroll 103 and the upper bracket 102, wherein the low-pressure cavity is communicated with the suction cavity when the scroll compressor sucks air, and the high-pressure cavity is communicated with the exhaust cavity when the scroll compressor exhausts air.

The scroll compressor oil return device that this embodiment disclosed includes: a first passage 106 formed in the fixed scroll 103 in the axial direction of the scroll compressor, a second passage 107 formed in the upper bracket 102 in the axial direction of the scroll compressor, and a third passage 108 formed in the stator 105 in the axial direction of the scroll compressor; and at least one capillary 201, wherein the capillary 201 is provided with a first through groove 202 along the axial direction of the scroll compressor.

The first passage 106, the second passage 107 and the third passage 108 are communicated to form an oil return passage. The oil return passage communicates between the oil sump 109 in the discharge chamber and the oil sump 110 of the scroll compressor, the oil sump 110 being generally located at the bottom of the scroll compressor. I.e., the lubrication oil in the discharge chamber is led back to the oil sump 110 at the bottom of the scroll compressor through the oil return passage. The location of the oil sump 110 within the scroll compressor is not limited by the present application. The oil return management is realized through the axial oil return channel, other oil return pipes do not need to be additionally arranged, the production cost is reduced, and meanwhile, the noise problem caused by the contact of the oil return pipes and the compressor shell is also avoided. In particular, the motor stator 105 of the existing partial scroll compressor has an axial through hole, so that the machining process can be further reduced, and the process efficiency can be improved.

On the other hand, through the axial oil return pipeline, the lubricating oil directly flows back to the oil pool 110 of the scroll compressor from the oil pool 109 in the exhaust cavity through the through hole on the side wall of the motor stator 105, so that the lubricating oil can be prevented from entering the pipeline of the air conditioning system along with compressed gas, the refrigeration and heating efficiency of the air conditioner is influenced, and the normal operation of the compressor can be influenced in serious cases; and the problem of lubrication and oil shortage of the compressor caused by a large amount of consumption of the low-pressure cavity engine oil can be avoided, and the working reliability of the compressor is improved.

In order to throttle the high-pressure gas and ensure the pressure difference between the two ends of the oil return passage, at least one of the first passage 106, the second passage 107 and the third passage 108 is provided with the capillary 201. Specifically, an oil return passage is formed by communicating the capillary 201 installed in the first passage 106, the second passage 107, or the third passage 108 with other passages not installed with the capillary 201. In this embodiment, the capillary 201 is installed in each of the first channel 106, the second channel 107, and the third channel 108, but the present application is not limited thereto. In practice, a person skilled in the art may install the capillary 201 in only one of the first channel 106, the second channel 107 and the third channel 108, or may install the capillary 201 in any two channels.

That is, the capillary 201 in the present embodiment has three capillaries, which are respectively a first capillary, a second capillary and a third capillary. The cross-sectional shapes of the first capillary, the second capillary, and the third capillary are all circular, the cross-sectional shapes of the first through grooves 202 in the first capillary, the second capillary, and the third capillary are all circular, and the cross-sectional shape of the first through groove 202 is a cross-sectional shape perpendicular to the longitudinal extension direction of the first through groove 202. The diameters of the first through grooves 202 in the first capillary, the second capillary, and the third capillary are equal to each other.

As shown in fig. 2 and 3, the capillary 201 in this embodiment is formed by two cylindrical rods with a semicircular cross section, and the two cylindrical rods have a semicircular groove in the cross section, and the grooves in the two cylindrical rods surround to form the first through groove 202, and the cross section of the cylindrical rods is parallel to the cross section of the first channel 106. That is, the outer surfaces of the two semi-cylindrical rods are respectively processed inwards to form a through groove with a semi-circular cross section or other shapes, and then the two semi-cylindrical rods are combined together to form a capillary 201 comprising the through groove with a circular cross section. The combined capillary 201 is put into the first channel 106, the second channel 107 or the third channel 108 which is processed in advance, and the throttling of the high-pressure gas can be realized. Because the through groove on the surface of the semi-cylindrical rod piece is obtained by external machining, the semi-cylindrical rod piece is not limited by machining size. The problem that the inner diameter of the capillary 201 cannot reach below 1mm, namely less than 1mm, due to the fact that the capillary 201 is obtained by directly drilling in the prior art is solved.

In this embodiment, the value range of the diameter of the first through groove 202 is 0.3mm to 0.6mm, and the setting of the capillary 201 with a smaller inner diameter can ensure that the pressure of the high-pressure cavity cannot drop, avoid influencing the pressure of the high-pressure cavity, and ensure the normal operation of the compressor and the oil return capacity of the compressor. The inner diameter value intervals of the first channel 106, the second channel 107 and the third channel 108 are all 2mm to 4mm, but the value ranges of all the inner diameters are not limited in the application, and can be set by a person skilled in the art as required.

In this embodiment, the cross section of the first through groove 202 is circular, the cross sections of the first channel 106, the second channel 107, and the third channel 108 are all circular, and the cross section of the first through groove 202 is a cross section of the first through groove 202 perpendicular to the longitudinal extension direction thereof. The cross section of the first channel 106 is a cross section of the first channel 106 perpendicular to the longitudinal extension direction thereof, and the cross sections of the first channel 106, the second channel 107 and the third channel 108 are parallel. However, the present application is not limited thereto.

In this embodiment, the first passage 106 and the second passage 107 are hermetically connected by an O-ring, which is beneficial to preventing the leakage of the lubricating oil in the oil return passage.

In another embodiment of the present invention, the inner diameters of the first channel 106, the second channel 107 and the third channel 108 are different, wherein the inner diameter of the first channel 106 is 2.5mm to 5mm, the inner diameter of the second channel 107 is 2mm to 4mm, and the inner diameter of the third channel 108 is 2mm to 6 mm. In other embodiments, the inner diameters of the first channel 106, the second channel 107, and the third channel 108 may be the same, which is not limited in this application.

In another embodiment of the present invention, as shown in fig. 4 and 5, the first through groove 202 is formed by recessing inward from the outer surface of the capillary 201, the cross section of the first through groove 202 is an arc shape, and the cross section of the first through groove 202 is parallel to the cross section of the first channel 106.

In another embodiment of the present invention, the capillary 201 is a cylindrical member with an annular cross section, the cross section of the first through groove 202 is a circle, the outer diameter of the capillary 201 is equal to the inner diameters of the first channel 106, the second channel 107 and the third channel 108, and the cross section of the capillary 201 and the cross section of the first through groove 202 are parallel to the cross section of the first channel 106.

In summary, the oil return device of the scroll compressor of the present invention has at least the following advantages:

according to the oil return device of the scroll compressor disclosed by the embodiment, the passages are respectively formed in the side walls of the fixed scroll, the upper bracket and the motor stator along the axial direction and are communicated to form the oil return passage, so that the lubricating oil in the exhaust cavity is guided back to the oil pool at the bottom of the scroll compressor, effective oil return management is realized, an oil return pipe is avoided being additionally arranged, the production cost of the compressor is reduced, and the structure is simplified;

In the description of the present invention, it is to be understood that the terms "bottom", "longitudinal", "lateral", "upper", "lower", "front", "rear", "vertical", "horizontal", and the like, indicate orientations and positional relationships based on the orientations and positional relationships shown in the drawings, are used only for convenience in describing the present invention and for simplification of description, and do not indicate or imply that the structures or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, are not to be construed as limiting the present invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more and "several" means one or more unless otherwise specified.

In the description herein, references to the description of "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," etc., indicate that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. An oil return device of a scroll compressor comprises an upper cylinder cover (101), an upper bracket (102), a fixed scroll (103), a movable scroll (104) and a motor, wherein an exhaust cavity is formed between the upper cylinder cover (101) and the fixed scroll (103), and the motor comprises a stator (105); characterized in that the device comprises:

a first passage (106) formed in the fixed scroll (103) in the axial direction of the scroll compressor,

a second channel (107) which is arranged on the upper bracket (102) along the axial direction of the scroll compressor,

a third channel (108) which is arranged on the stator (105) along the axial direction of the scroll compressor; and

the scroll compressor comprises at least one capillary tube (201), wherein a first through groove (202) is formed in the capillary tube (201) along the axial direction of the scroll compressor;

at least one of the first channel (106), the second channel (107) and the third channel (108) is mounted with the capillary (201); the first channel (106), the second channel (107) and the third channel (108) are communicated to form an oil return channel; the oil return passage communicates an oil sump (109) of the discharge chamber with an oil sump (110) of the scroll compressor.

2. The scroll compressor oil return device according to claim 1, wherein the cross sections of the first channel (106), the second channel (107) and the third channel (108) are all circular, the cross section of the first channel (106) is a cross section of the first channel (106) perpendicular to the length extension direction of the first channel, and the cross sections of the first channel (106), the second channel (107) and the third channel (108) are parallel.

3. The scroll compressor oil return device according to claim 2, wherein the capillary tube (201) is a cylindrical member with an annular cross section, the cross section of the first through groove (202) is a circular shape, the outer diameter of the capillary tube (201) is equal to the inner diameter of the first passage (106), the second passage (107) and the third passage (108), and the cross section of the capillary tube (201) and the cross section of the first through groove (202) are parallel to the cross section of the first passage (106).

4. The scroll compressor oil return apparatus of claim 2 wherein said capillary tube (201) is defined by two cylindrical rods having a semi-annular configuration in cross-section, said cylindrical rods having a semi-circular groove in cross-section, and wherein said grooves in said two cylindrical rods define said first channel (202) in said cross-section parallel to said first passage (106) in cross-section.

5. The scroll compressor oil return apparatus of claim 2, wherein the first through slot (202) is formed recessed inwardly from an outer surface of the capillary tube (201), a cross section of the first through slot (202) is an arc, and a cross section of the first through slot (202) is parallel to a cross section of the first passage (106).

6. The scroll compressor oil return apparatus of claim 1 wherein said first passage (106) is sealingly connected to said second passage (107) by an O-ring seal.

7. The scroll compressor oil return apparatus of claim 1 wherein said capillary tube (201) has three, a first capillary tube, a second capillary tube and a third capillary tube; the cross section shapes of the first through grooves (202) in the first capillary, the second capillary and the third capillary are all circular, and the cross section of each first through groove (202) is a cross section, perpendicular to the length extending direction, of the corresponding first through groove (202).

8. The scroll compressor oil return apparatus of claim 7 wherein the first through slot (202) in the first, second and third capillary tubes are of equal diameter.

9. The oil return device for the scroll compressor according to claim 2, wherein the inner diameters of the first passage (106), the second passage (107) and the third passage (108) are all 2mm to 4 mm.

10. The oil return device of the scroll compressor as claimed in claim 1, wherein the cross section of the first through groove (202) is circular, the diameter of the first through groove (202) ranges from 0.3mm to 0.6mm, and the cross section of the first through groove (202) is the cross section of the first through groove (202) perpendicular to the length extension direction of the first through groove.