Electric Compressor

Abstract

To provide an electric compressor in which an oil separator can be molded integrally into a rear housing. [Solution] The electric compressor of the present invention includes a front housing that defines the outer shape and is formed at the position of the suction port through which the refrigerant is drawn, a compression unit that compresses the refrigerant by receiving rotational force generated by a drive unit, and a rear housing in which a discharge chamber in which the refrigerant compressed by the compression unit accumulates and a discharge path through which the refrigerant in the discharge chamber is discharged to the outside are formed, and is characterized in that an oil separation section is formed on the inner wall on the discharge path, and the oil separation section is formed in an uneven shape along the rotation direction of the refrigerant on the discharge path. The depth of a first groove section formed in the oil separation section becomes deeper the farther from the discharge hole along the rotation direction of the refrigerant, so that the oil contained in the refrigerant is separated.

Description

[Technical field]

[0001] The present invention relates to a compressor for separating oil contained in a refrigerant discharged from the compressor, and more particularly to an electric compressor having improved oil separation performance for separating oil contained in a refrigerant. [Background technology]

[0002] In general, an air conditioner installed in a vehicle is composed of a compressor, a condenser, an expansion valve, and an evaporator. The compressor compresses the refrigerant gas discharged from the evaporator into a high-temperature, high-pressure state that is easy to liquefy, and delivers it to the condenser. The compressor also pumps and recirculates the refrigerant so that the air conditioner can continue to be cooled. The condenser liquefies the high-temperature, high-pressure refrigerant gas by exchanging heat with the outside air, and the expansion valve adiabatically expands the liquid refrigerant to reduce its temperature and pressure, making it easy to evaporate in the evaporator. The evaporator exchanges heat between the liquid refrigerant and the outside air introduced into the vehicle interior, absorbing and evaporating heat. The outside air is cooled by the refrigerant absorbing heat, and is blown into the vehicle interior by a blower. Compressors are classified into two types: a reciprocating type in which the part that compresses the working fluid (refrigerant) reciprocates to compress the fluid, and a rotary type in which the part rotates to compress the fluid. The reciprocating type includes a crank type in which a crank is used to transmit the driving force of a drive source to multiple pistons, a swash plate type in which the driving force is transmitted to a rotating shaft equipped with a swash plate, and a wobble plate type that uses a wobble plate.

[0003] As an example, a scroll compressor is a type of rotary compressor, and refers to a compressor in which compression is performed while two meshed scrolls with involute teeth perform an orbital motion. The scroll compressor operates while a rotating scroll and a fixed scroll, which have a geometric phase difference of 180, rotate relative to each other inside a discharge chamber, and the rotating scroll and the fixed scroll have scroll-shaped wraps, and the wraps are formed of an involute curve having the same shape. In the scroll compressor, a crescent-shaped compression chamber is formed by the meshing of the rotating scroll and the fixed scroll, and a compression cycle is performed. The compression chamber is formed in a shape in which the volume is larger toward the outside and smaller toward the center, and a suction chamber is formed on the outside and a discharge port is formed in the center.

[0004] In the scroll compressor, the size of the compression space gradually decreases toward the discharge port due to the relative rotation of the scroll and the intake gas sealed in the sealed space of a volume given to the outer periphery of the scroll, and the refrigerant is discharged through the discharge port. The refrigerant discharged from the discharge chamber is centrifuged through an oil separator, and then finally discharged through a discharge port.

[0005] Conventional oil separators are manufactured by drilling a discharge passage to a predetermined depth inside a rear housing of a scroll compressor, and then inserting an oil ring into the oil separator. In this case, the oil separation efficiency is reduced as the oil flows into the oil separator and moves through the discharge passage, resulting in a problem that the refrigerant moves to the evaporator with oil remaining in the refrigerant. In this case, the evaporation efficiency of the refrigerant in the evaporator is reduced, which affects the efficiency of the compressor. Summary of the Invention [Problem to be solved by the invention]

[0006] In this embodiment, an oil separator structure forming means having an oil separator shape is inserted into the rear housing in advance when the rear housing is manufactured by casting, and when the casting of the rear housing is completed, the oil separation structure forming means can be easily separated to provide an electric compressor in which an oil separator integrated into the rear housing can be formed. [Means for solving the problem]

[0007] The electric compressor according to the present invention includes a front housing having an outer shape and formed at the position of an intake port through which a refrigerant is drawn, a compression unit which compresses the refrigerant by transmitting rotational force generated by a drive unit, and a rear housing in which a discharge chamber in which the refrigerant compressed by the compression unit accumulates and a discharge path through which the refrigerant in the discharge chamber is discharged to the outside, and is characterized in that an oil separation portion is formed on an inner wall on the discharge path, and the oil separation portion is formed in an uneven shape along the rotational direction of the refrigerant on the discharge path.

[0008] The oil separation section is characterized in that the depth of a portion formed in an uneven shape along a rotation direction of the refrigerant is variable.

[0009] The oil separation section is characterized in that a depth of a portion formed in an uneven shape along a rotation direction of the refrigerant becomes deeper.

[0010] The oil separation section extends so as to be inclined inwardly as it goes downward in the longitudinal direction.

[0011] The rear housing includes an oil separation plate located above the oil separation unit for further separating oil contained in the refrigerant.

[0012] The rear housing is formed with a locking step on which the oil separation plate is seated.

[0013] The oil separation plate includes a main body portion having an open upper surface, and a refrigerant passage hole formed on the inner lower surface of the main body portion so that the gaseous refrigerant from which oil has been removed by the oil separation portion can move.

[0014] The refrigerant passage hole has an inner diameter that increases from a lower surface to an upper surface of the main body portion.

[0015] The main body portion further includes an auxiliary oil separator formed in an inner longitudinal direction.

[0016] The rear housing is characterized in that a bush is disposed on an upper surface of the oil separation plate.

[0017] The bush has an opening formed therein for allowing a refrigerant to pass therethrough, and the opening is formed to be smaller than the inner diameter of the oil separation plate.

[0018] The oil separation plate has an inner lower surface formed in a mash shape.

[0019] The oil separation portion is disposed below the rear housing in opposition to a discharge hole formed in the rear housing, and the oil separation plate is disposed above the discharge hole at a distance.

[0020] The compressed refrigerant flows to an oil separation section through a discharge hole formed in the rear housing.

[0021] The oil separation portion is formed by an oil separation structure forming means when the rear housing is cast.

[0022] The oil separation structure forming means includes a first body portion which defines the overall outer shape, has a communicating hole which communicates with the discharge hole, and has grooves and protrusions formed repeatedly in the longitudinal direction, a second body portion which extends above the first body portion and has an outer diameter which is relatively larger than the outer diameter of the first body portion, and a locking step forming portion which is formed on an inner lower end of the second body portion.

[0023] The oil separation portion includes a first groove portion formed inside a discharge wall portion which is cast together with the oil separation structure forming means to form the overall outer shape, the first groove portion being formed at a position corresponding to the protrusion, and a first protrusion portion being formed at a position corresponding to the groove portion of the oil separation structure forming means.

[0024] The oil separation section is composed of a first section that extends vertically from the communication hole to the lower end of the first body section, and a second section that extends a predetermined length from the upper side of the first section to the upper end of the second body section. Effect of the Invention

[0025] In this embodiment, when the rear housing is molded by a casting method, the oil separator can be molded by the oil separation structure forming means, which makes manufacturing easier and reduces costs by eliminating the drilling process. In this embodiment, when oil separation is performed by the oil separation structure forming means, the oil contained in the refrigerant moves and separates in a state where the contact area of ​​the oil is increased, which improves the efficiency of oil separation. In this embodiment, after the refrigerant discharged from the compressor flows in, the oil contained in the refrigerant is separated by the centrifugal separation principle, and only the refrigerant gas can move through the discharge hole, which improves the efficiency of oil separation. [Brief description of the drawings]

[0026] [Figure 1] 1 is a vertical sectional view of an electric compressor according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective view showing an oil separation structure forming means according to an embodiment of the present invention. [Diagram 3] 2 is a vertical cross-sectional view of a rear housing provided with an oil separation unit and main components according to an embodiment of the present invention. FIG. [Figure 4] 5A and 5B are diagrams illustrating paths along which a refrigerant moves inside a rear housing according to the present embodiment. [Diagram 5] FIG. 4 is a view showing the inside of a rear housing according to the present embodiment. [Figure 6] FIG. 2 is a vertical cross-sectional view of the oil separation plate according to the present embodiment. [Figure 7] FIG. 4 is a perspective view showing another embodiment of the oil separation plate according to the present embodiment. [Figure 8] FIG. 2 is a perspective view showing an embodiment in which the inside of the oil separation plate according to the present invention is mash-like. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The present invention can be modified in various ways and can have various embodiments, and a specific embodiment will be described in detail with reference to the drawings. However, this is not intended to limit the present invention to a specific embodiment, and it should be understood that the present invention includes all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. The thickness of lines and the size of components shown in the accompanying drawings may be exaggerated for clarity and convenience of explanation.

[0028] In addition, the terms described below are defined in consideration of the functions of the present invention, and may change depending on the intention of a user or operator or legal precedent. Therefore, the definitions of such terms should be based on the contents of the entire specification.

[0029] The electric compressor according to the present embodiment will be described with reference to the drawings.

[0030] As reference drawings, FIG. 1 is a longitudinal sectional view of an electric compressor according to one embodiment of the present invention, FIG. 2 is a perspective view showing an oil separation structure forming means according to one embodiment of the present invention, FIG. 3 is a longitudinal sectional view of a rear housing provided with an oil separation section and main components according to one embodiment of the present invention, FIG. 4 is a diagram showing the path along which refrigerant moves inside the rear housing according to this embodiment, and FIG. 5 is a diagram showing the inside of the rear housing according to this embodiment.

[0031] 1 to 5, the electric compressor (1) according to this embodiment is configured with a front housing (2a) that defines an outer shape and is formed at the position of a suction port through which a refrigerant is drawn, a middle housing (2b), and a rear housing (2), and a drive section (3) and a compression unit (5) are built in the middle housing (2b). The drive section (3) is configured to include a stator, a rotor, and a rotating shaft (4) inserted in the center of the rotor.

[0032] The drive unit (3) generates a rotational force and transmits it to the compression unit (5), which compresses and discharges the refrigerant. The compression unit (5) includes a fixed scroll and a rotating scroll, the fixed scroll being maintained in a fixed state, the orbiting scroll being eccentrically rotatable with respect to the fixed scroll, and compresses the refrigerant while moving relative to the fixed scroll. The rear housing (2) is located at one side end of the intermediate housing (2b), and more specifically, is selectively and removably attached to the intermediate housing (2b) in a state where it is coupled to the right end with respect to the drawing.

[0033] The refrigerant discharged from the compression unit (5) moves through the discharge hole (12) formed in the rear housing (2) after being discharged by the compression unit (5), and rotates along the oil separation section (22), thereby separating the oil contained in the refrigerant. In particular, in this embodiment, when the oil separation section (22) is molded in the rear housing (2) by a casting method using the oil separation structure forming means (20), the oil separation section (22) is positioned inside the rear housing (2) and molded together, thereby improving the workability of the operator.

[0034] In addition, in this embodiment, the oil separation structure forming means 20 is used to minimize additional work after casting the rear housing 2, and tolerance control of the space where oil separation occurs is easy when manufacturing the rear housing 2, improving design freedom. The oil separation structure forming means 20 is used to form an oil separation section 22 in the rear housing 2 that is capable of separating oil.

[0035] In particular, in this embodiment, when molding the rear housing (2), the worker can easily insert the oil separation structure forming means (20), thereby improving manufacturability, eliminating the need for additional work such as a drilling process, reducing costs, and improving worker operability.

[0036] The oil separation structure forming means 20 extends with a length and structure as shown in the drawings so as to form an oil separation section 22 that separates foreign matter contained in oil, and when it is separated after the casting of the rear housing 2 is completed without performing additional work on the rear housing 2 by drilling, further drilling is not required, which can reduce costs and improve the workability of workers. The oil separation structure forming means 20 is formed as a cylindrical space formed with a predetermined length as shown in the drawings, and the length of its axial extension can be changed in various ways.

[0037] The oil separation structure forming means (20) according to this embodiment includes a first body portion (21) which defines the overall outer shape, has a communication hole (24a) which communicates with the discharge hole (12) and has grooves (21a) and protrusions (21b) formed repeatedly in the length direction, a second body portion (24) which extends above the first body portion (21) and has an outer diameter relatively larger than that of the first body portion (21), and a locking step forming portion (23) formed at the inner lower end of the second body portion. The first body portion (21) extends longer than the second body portion (24), and the second body portion (24) has an outer diameter relatively larger than that of the first body portion (21), and has a locking step forming portion (23) formed at the inner lower portion which forms a structure for receiving an oil separation plate (28) described later.

[0038] The first body part (21) is formed in the shape shown in the drawing so as to be easily inserted into and separated from the rear housing (2), and extends in the length direction as shown in the drawing with the grooves (21a) and protrusions (21b) repeated in the circumferential direction. The first body part (21) forms an oil separation part (22) to be described later with the grooves (21a) and protrusions (21b), and the oil contained in the refrigerant can be separated by the grooves (21a) and protrusions (21b). The oil separation structure forming means (20) is composed of a first section (S1) that extends vertically to the lower end of the first body part (21) and a second section (S2) that extends a predetermined length from the upper side of the first section (S1) to the upper end of the second body part (24) among the entire section (S) extending in the length direction.

[0039] The oil-separating structure forming means (20) is divided into a first section (S1) and a second section (S2) based on the locking step forming portion (23), so that the position does not change during the casting process after being positioned in the rear housing (2). Even if an operator positions it inside the rear housing (2), the installation work can be performed without any need for mounting. The oil-separating portion (22) includes a first groove portion (22a) formed at a position corresponding to the protrusion portion (21b) on the inside of the discharge wall portion (22c) which is cast together with the oil-separating structure forming means (20) and forms the overall outer shape, and a first protrusion portion (22b) formed at a position corresponding to the groove portion (21a) of the oil-separating structure forming means (20).

[0040] The first groove portion (22a) and the first protrusion portion (22b) are formed on the inside of the discharge wall portion (22c), and the depth of the first groove portion (22a) is increased along the direction of rotation of the refrigerant, so that the oil contained in the refrigerant, which has a high specific gravity, moves downward due to collision and contact, and only the gaseous refrigerant, which has a relatively low specific gravity, is easily separated. A more detailed explanation of the oil separation portion (22) will be given later. When the oil separation structure forming means (20) is formed by casting, the oil separation portion (22) (see FIGS. 4 and 5) is easily formed on the inside of the rear housing (2), so that the rear housing (2) having the oil separation portion (22) can be manufactured by one casting without an additional operation for oil separation.

[0041] The rear housing (2) is provided with an oil separation plate (28) located above the oil separation section (22) for further separating oil contained in the refrigerant. The oil separation plate (28) can be seated on the locking step (22d) and is fixed in position as soon as it is inserted, making installation easy. The oil separation plate (28) is provided to further separate oil contained in the refrigerant that has not been separated by the oil separation section (22). The oil separation plate (28) includes a main body section (28a) formed in a cylindrical shape with an open upper surface, and a refrigerant passing hole (28b) formed on the lower surface inside the main body section (28a) so that the gaseous refrigerant from which oil has been removed by the oil separation section (22) can move.

[0042] The refrigerant passing holes (28b) are arranged at regular intervals with a predetermined diameter as shown in the drawing, and the speed of the refrigerant gas passing through them is reduced, so that the unseparated oil is separated from the refrigerant gas. The refrigerant gas does not experience resistance before passing through the oil separation plate (28), but the speed of the refrigerant gas passing through the refrigerant passing holes (28b) is reduced, so that the oil remaining in the refrigerant gas can be further separated. In the rear housing (2), a bush (29) is arranged on the upper surface of the oil separation plate (28), and for example, the bush (29) is formed in a ring shape, so that the unseparated excess oil can be further separated from the oil separation plate (28).

[0043] The bushing (29) has an opening (29a) for allowing the refrigerant to pass through, and the opening (29a) is formed smaller than the inner diameter of the oil separation plate (28), so that further oil separation can be performed. In particular, the bushing (29) can more easily guide the oil to fall because the refrigerant gas moves through the opening (29a) after colliding with the lower surface of the bushing (29) rather than passing through the bushing (29) as it is. The bushing (29) may have a thread on the outside to make it easier for an operator to assemble it.

[0044] When the rear housing 2 is cast by the oil separation structure forming means 20, an oil separation section 22 is formed inside the rear housing 2 facing the discharge hole 12, and an oil separation plate 28 is attached above the discharge hole 12 at a distance. The oil separation section 22 is deeper the farther it is from the discharge hole 12 in the rotation direction of the refrigerant, so that the oil contained in the refrigerant can be stably separated due to the increase in the rotational force of the oil and the contact area. The refrigerant contains pure gaseous refrigerant and oil, and the oil contained in the refrigerant is separated into refrigerant gas and oil after moving to the rear housing 2, and some foreign matter contained in the oil moves downward together with the oil.

[0045] The refrigerant flows in through the discharge hole (12) and then rotates in the inner circumferential direction in a direction A away from the discharge hole (12) at a predetermined speed while coming into contact with the oil separation section (22) under centrifugal force. As shown in the cross-sectional view, the oil separation section (22) is formed such that the first groove section (22a) gradually becomes deeper along the discharge wall section (22c) from a position adjacent to the discharge hole (12) in the direction of refrigerant rotation. Therefore, the oil contained in the refrigerant flows into the first groove section (22a) and collides with the inner surface, so that the oil can easily move downward in the direction of gravity. The reason why the oil separation section (22) is formed as described above is that when the refrigerant flows through the discharge hole (12) and through the communication hole (24a) and the depth at position a of the oil separation section (22) is formed as shown in the figure, the refrigerant diffuses at the position and comes into contact with the inner surface, which increases the area, thereby allowing oil separation to be performed more smoothly.

[0046] In this embodiment, in order to maximize this effect, the depth is gradually increased as the position moves from a to b and c, so that the contact area with the refrigerant gradually increases along with the centrifugal force due to rotation, thereby inducing stable centrifugation, and thus improving the efficiency of separating oil contained in the refrigerant. For example, the refrigerant moves along the direction of rotation, and at position d, the contact area of ​​the oil separator (22) increases the most and collides, and the oil with a high specific gravity moves downward in the direction of gravity and then moves to the back pressure chamber and suction chamber side by the pressure difference through a separately formed passage (not shown).

[0047] The oil separation part (22) extends inwardly in a longitudinal direction so as to be inclined downwardly, and improves the downward mobility of the oil contained in the refrigerant, thereby improving the efficiency of oil separation. Referring to the attached Fig. 6, the refrigerant passing hole (28b) according to this embodiment is formed so that the inner diameter is kept constant or the inner diameter increases from the lower surface to the upper surface of the main body part (28a).

[0048] When the inner diameter of the refrigerant passing hole (28b) is enlarged as described above, the movement speed of the refrigerant gas decreases, and the oil can be further separated through surface contact with the inner surface of the refrigerant passing hole (28b), thereby further improving the efficiency of oil separation. The oil separation plate (28) extends a predetermined length upward from the lower surface of the inner side of the main body portion (28a) to form a space on the inside, and the refrigerant gas diffuses in the space, thereby further separating the oil contained in the refrigerant gas that has passed through the refrigerant passing hole (28b).

[0049] Referring to FIG. 7, the main body portion (28a) according to this embodiment further includes an auxiliary oil separation groove (28c) formed in the inner longitudinal direction, and the auxiliary oil separation groove (28c) guides excess oil contained in the refrigerant gas passing through the above-mentioned refrigerant passing hole (28b) to be separated through surface contact with the auxiliary oil separation groove (28c). 8, the oil separation plate (28) according to the present embodiment has an inner lower surface formed in a mash shape. When the oil separation plate (28) is formed in a mash shape in this manner, the plates are closely spaced apart, thereby improving the efficiency of separating oil contained in the refrigerant gas.

[0050] Although one embodiment of the present invention has been described above, a person having ordinary knowledge in the relevant technical field may modify and change the present invention in various ways by adding, changing, deleting or adding components within the scope of the concept of the present invention described in the claims, and this also falls within the scope of the claims of the present invention. [Industrial Applicability]

[0051] This embodiment can be applied to an electric compressor that requires oil separation. [Explanation of symbols]

[0052] 1 Electric compressor 2 Rear housing 2a Front housing 2b Intermediate housing 3 Drive unit 4 Rotation Axis 5 Compression Unit 12 Discharge hole 20 Oil separation structure forming means 21 First Body Section 21a Groove 21b Protrusion 22 Oil separation section 22a 1st groove 22b 1st protrusion 22c Discharge wall section 22d Locking step 23 Locking step forming part 24 Second Body Section 24a Communication hole 28 Oil separation plate 28a Main body section 28b Refrigerant passage hole 28c Auxiliary oil separation groove 29 Bush 29a Opening hole

Claims

1. a front housing having an outer shape and formed at a position of an intake port through which a refrigerant is drawn; a compression unit that compresses a refrigerant by receiving a rotational force generated by the drive unit; a rear housing having a discharge chamber in which the refrigerant compressed by the compression unit accumulates and a discharge path through which the refrigerant in the discharge chamber is discharged to the outside, an oil separation portion is formed on an inner wall of the discharge path, The oil separation portion is formed in an uneven shape along a rotation direction of the refrigerant on the discharge path, The oil separation section has a depth of a portion formed in an uneven shape along a rotation direction of the refrigerant, The electric compressor, wherein the oil separation section has a portion formed in an uneven shape with a depth increasing along a rotation direction of the refrigerant.

2. The electric compressor according to claim 1 , wherein the oil separation portion extends so as to be inclined inwardly as it goes downward in the longitudinal direction.

3. 3. The electric compressor according to claim 2, wherein the rear housing includes an oil separation plate located above the oil separation section for further separating oil contained in the refrigerant.

4. 4. The electric compressor according to claim 3, wherein the rear housing is formed with a locking step on which the oil separation plate is seated.

5. The oil separation plate includes a main body portion having an open upper surface, 5. The electric compressor according to claim 4, further comprising: a refrigerant passage hole formed in an inner lower surface of the main body portion through which the gaseous refrigerant from which oil has been removed by the oil separation portion moves.

6. 6. The electric compressor according to claim 5, wherein an inner diameter of the refrigerant passage hole increases from a lower surface to an upper surface of the main body portion.

7. 7. The electric compressor of claim 6, wherein the main body portion further comprises an auxiliary oil separator formed in an inner longitudinal direction.

8. 4. The electric compressor according to claim 3, wherein the rear housing has a bush disposed on an upper surface of the oil separation plate.

9. 9. The electric compressor according to claim 8, wherein the bush has an opening through which the refrigerant passes, the opening having a diameter smaller than an inner diameter of the oil separation plate.

10. The electric compressor according to claim 9, wherein the oil separation plate has an inner lower surface formed in a mesh shape.

11. 4. The electric compressor according to claim 3, wherein the oil separation section is disposed on a lower side of the rear housing opposite to a discharge hole formed in the rear housing, and the oil separation plate is disposed on an upper side of the discharge hole at a distance.

12. The electric compressor according to claim 11, wherein the compressed refrigerant flows to an oil separation section through a discharge hole formed in the rear housing.

13. 2. The electric compressor according to claim 1, wherein the oil separation portion is formed by an oil separation structure forming means when the rear housing is cast.

14. The oil separation structure forming means includes a first body portion that defines an overall outer shape, a communication hole that communicates with the discharge hole, and grooves and protrusions that are repeatedly formed in a longitudinal direction; a second body portion extending above the first body portion and having an outer diameter relatively larger than an outer diameter of the first body portion; The electric compressor according to claim 13, further comprising: a locking step formed at an inner lower end of the second body portion.

15. The oil separation portion includes a first groove portion formed at a position corresponding to the protrusion on the inside of a discharge wall portion that is cast together with the oil separation structure forming means to form an overall outer shape, and 15. The electric compressor according to claim 14, further comprising: a first protrusion formed at a position corresponding to the groove of the oil separation structure forming means.

16. 15. The electric compressor of claim 14, wherein the oil separation section includes a first section extending vertically from the communication hole to a lower end of the first body section, and a second section extending a predetermined length from an upper side of the first section to an upper end of the second body section.

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