CN212389517U

CN212389517U - Compressor

Info

Publication number: CN212389517U
Application number: CN202020912403.4U
Authority: CN
Inventors: 柳庆重; 金政勋
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2019-08-12
Filing date: 2020-05-26
Publication date: 2021-01-22
Anticipated expiration: 2030-05-26
Also published as: KR102308157B1; KR20210019640A

Abstract

The utility model relates to a compressor. In the utility model discloses in, through to constituting the at least some in the contact surface between the rotation axis (30) and the bearing of compressor, the contact surface between rotation axis (30) and compression unit (50) and the contact surface between the revolution mechanic of compression unit (50), carry out surface treatment and form minute slot portion. That is, the present invention can reduce friction by forming the fine groove (D) by treating the surface of the member that generates friction among the members constituting the compressor.

Description

Compressor

Technical Field

The present invention relates to a compressor, and more particularly, to a compressor that reduces friction loss generated during operation.

Background

Generally, a compressor is a device for generating high pressure or delivering high pressure fluid, and when applied to a compressor of a refrigeration cycle such as a refrigerator or an air conditioner, the compressor functions to compress a refrigerant and send the refrigerant to a condenser. Such compressors are classified into reciprocating compressors, rotary compressors, scroll compressors, and the like according to a method of compressing refrigerant gas.

Such a compressor compresses a refrigerant sucked into a compression chamber by a rotational force of a motor and then discharges the compressed refrigerant. The rotational force of the motor is transmitted to the compression chamber through the rotational shaft, and friction is generated between various components during the rotation. For example, in the case of a scroll compressor, friction is generated between a rotating shaft and an orbiting scroll, and friction is also generated between the orbiting scroll and a fixed scroll. In addition, friction is also generated between the bearing supporting the rotating shaft and the rotating shaft.

This friction results in friction losses and reduces the energy efficiency of the compressor. In order to solve such a problem, a method of reducing the friction coefficient by machining the friction surface (contact surface) is conceivable, but the surface machining of the compressor member made of a metal material has a disadvantage of complicated processing steps or high cost. For example, in order to improve the lubricating property by machining the friction surface, a special composition is subjected to surface treatment or laser machining, which has a problem of reducing the yield and greatly increasing the cost.

Korean laid-open patent No. 10-2014-0001700

SUMMERY OF THE UTILITY MODEL

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to reduce friction generated between components during operation of a compressor.

Another object of the present invention is to reduce the friction force of a member by physically treating a friction surface (contact surface) of the member constituting a compressor.

A compressor, comprising: a casing, a refrigerant suction pipe for sucking the refrigerant connected with the inner space; a rotating shaft which is rotated by a driving unit and is rotatably supported in the inner space by a bearing; and a compression unit that compresses a refrigerant by rotating the rotary shaft in an inner space of the casing, wherein at least a part of a contact surface between the rotary shaft and a bearing, a contact surface between the rotary shaft and the compression unit, and a contact surface between rotary structures of the compression unit is formed with fine grooves formed by surface treatment.

In order to achieve the above object, according to the present invention, the fine groove portion is formed by performing surface treatment on at least a part of a contact surface between a rotary shaft and a bearing constituting the compressor, a contact surface between the rotary shaft and the compression unit, and a contact surface between a rotary structure of the compression unit. That is, the friction force is reduced by forming the fine groove portions by treating the surface of a member generating friction among members constituting the compressor.

The minute groove portion may be formed by spraying fine particles of a metal or a non-metal onto the contact surface.

Further, a first shaft contact surface connected to a bearing is formed at one side of the rotating shaft, and a second shaft contact surface rotatably connected to the compression unit or another bearing is formed at the opposite side, the first shaft contact surface and the second shaft contact surface are respectively surface-treated to form fine grooves, and the surface-treated areas or the sizes of the fine grooves may be different from each other in the first shaft contact surface and the second shaft contact surface. Therefore, the contact surface having a large frictional force can further reduce the friction coefficient by increasing the minute groove portions.

At this time, the minute groove portions are formed in a groove shape having a diameter of 20 to 50 μm and a depth of 2 to 5 μm, and an oil film formed of oil may be formed at edges of the minute groove portions and inside of the minute groove portions. Therefore, when relative movement occurs between the components, the frictional characteristics can be further improved.

The compression unit includes: a fixed scroll fixedly disposed in the inner space; and a swirl disk connected to the rotary shaft and performing a swirling motion, a compression chamber being formed between the swirl disk and the fixed scroll by meshing with the fixed scroll, and a scroll contact surface having a fine groove portion formed on an outer surface thereof, at least a part of a top surface of a swirl portion constituting the swirl disk and a bottom surface of the fixed scroll portion closely contacting the top surface of the swirl portion and constituting the fixed scroll. Therefore, the friction coefficient of the compression unit can also be reduced.

Further, a shaft-bush contact surface is formed on at least one of the outer surface of the rotating shaft and the inner surface of the sliding bush, a scroll-bush contact surface is formed on at least one of the outer surface of the sliding bush and the inner surface of the coupling portion of the orbiting scroll, and fine groove portions are also formed on these contact surfaces, thereby reducing the friction coefficient.

According to another feature of the present invention, the present invention includes: a covering step of covering the periphery of the surface to be processed of the workpiece; a fixing step of fixing the workpiece; and a blasting step of blasting fine particles onto a surface to be processed, which is a contact surface, while rotating the member to be processed. Thus, the fine groove portions are formed by surface treatment on at least one of the contact surfaces between the members, whereby the frictional force can be reduced.

The compressor according to the present invention as described above has the following effects.

In the present invention, the friction force is reduced by processing the surface of the friction-generating member among the members constituting the compressor to form the fine groove portion. For example, the friction force is reduced by forming a fine groove portion at a contact surface between the rotary shaft and the bearing, a contact surface between the rotary shaft and the compression unit, or a contact surface between the rotary structures of the compression unit. The minute groove portion can not only reduce the friction surface but also form an oil film on the edge of the minute groove portion and the inside of the minute groove portion. Therefore, the frictional characteristics when relative movement occurs between the members can be improved, and as a result, the efficiency of the compressor can be improved.

In addition, in the present invention, in order to form the fine groove portion on the surface of the member, the contact surface is subjected to surface treatment, and in this case, the fine groove portion can be formed by spraying fine particles of metal or nonmetal onto the contact surface. That is, since the surface of the member is physically treated without applying a special composition or chemically treating the surface, the processing is simple and the processing cost is relatively low, thereby having an effect of improving the processing efficiency.

The micro groove portions manufactured as described above can be manufactured to have different sizes depending on the conditions of the contact surface, so that the friction coefficient of the component can be reduced. For example, the contact surface having a large friction force can further reduce the friction coefficient by increasing the minute groove portion, but the present invention forms the minute groove portion by injecting the fine particles, and therefore, the minute groove portion conforming to the condition of the contact surface and the friction coefficient corresponding thereto can be obtained by changing the size of the fine particles. Therefore, the compressor of the present invention can satisfy various conditions of the compressor by a simpler manufacturing method.

Further, according to the present invention, since the peripheral surface other than the contact surface processed into the minute groove portion can be processed into the non-processed surface by performing the simple covering work, the work for processing the minute groove portion on the surface of the contact surface can be accurately performed by a relatively simple method.

In particular, by rotating the member with the jig and spraying the fine particles, the fine groove portions can be uniformly formed on the processing surface, and the density of the fine groove portions can be changed when the rotation speed is adjusted. That is, since the friction coefficient of the compressor member can be set by adjusting the rotation speed of the jig, there is an effect that various conditions of the compressor can be satisfied.

Drawings

Fig. 1 is a sectional view showing an internal structure of an embodiment of a compressor of the present invention.

Fig. 2 is a sectional view illustrating a portion where friction is generated between components constituting the compressor in the embodiment shown in fig. 1.

Fig. 3 is a perspective view showing a part of components constituting the compressor in the embodiment shown in fig. 1, which is exploded.

Fig. 4 is a perspective view showing a structure of a rotary shaft constituting a compressor in the embodiment shown in fig. 1.

Fig. 5 is a perspective view showing a state in which the structure of the rotating shaft-sliding bush-swirling coil is exploded in the embodiment shown in fig. 1.

Fig. 6 is a perspective view showing a contact surface in which a fixed scroll and an orbiting scroll constituting a compression unit are exploded in the embodiment shown in fig. 1.

Fig. 7 is a perspective view showing a state in which a jig is coupled to process the rotating shaft shown in fig. 4.

Fig. 8A and 8B are perspective views each showing a machined surface of the slide bush in the embodiment shown in fig. 1.

Fig. 9 is an enlarged view comparing the surface of the rotary shaft constituting the compressor of the present invention with the surface before machining.

Description of reference numerals

10: a casing 20: drive unit

30: rotation shaft 35: eccentric convex part

37: sliding bush 40: main frame

50: the compression unit 60: fixed scroll

62: fixing plate 65: fixed scroll part

70: swirling disc 72: rotary plate

75: swirl coil

Detailed Description

In the following, some embodiments of the invention are explained in detail by means of exemplary drawings. Note that, when reference numerals are given to components in each drawing, the same components are denoted by the same reference numerals as much as possible even when they are denoted by different drawings. In describing the embodiments of the present invention, it is to be understood that specific descriptions of related well-known structures and functions will be omitted when it is determined that the detailed descriptions thereof will hinder the understanding of the embodiments of the present invention.

In addition, in describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), and the like may be used. The above terms are only used to distinguish the above-mentioned components from other components, and the nature, order, sequence, and the like of the corresponding components are not limited by the above terms. When it is stated that a certain component is "connected", "coupled" or "in contact with" another component, it is to be understood that the component may be directly connected or in contact with the other component, and that another component may be "connected", "coupled" or "in contact with" another component between the components.

The compressor of the embodiment of the present invention generally includes a casing 10, a driving unit 20, a compressing unit 50, a rotating shaft 30, and has a structure for improving efficiency by reducing a friction coefficient of a contact surface generating friction during an operation. Here, the contact surface refers to a frictional surface, and main contact portions are indicated by reference numerals (i) to (iv) in fig. 2. The structure of such a contact surface will be described in detail below.

For reference, a scroll compressor is described below as an example, but the present invention can also be applied to a rotary compressor or a swash plate compressor. That is, the present invention is applicable to various compressors including a driving unit 20 (motor), a rotating shaft 30 rotated by the driving unit 20, and a compressing unit 50 for changing the volume of a compressing chamber (V1, V2, see fig. 3) by the rotating shaft 30.

First, the casing 10 forms an external appearance of the compressor, and is formed with an internal space S1 therein. The internal space S1 is provided with a member for operating the compressor. The casing 10 includes a cylindrical main body case 11 opened in the up-down direction, an upper case 13 covering the upper portion of the main body case 11, and a lower case 17 covering the lower portion of the main body case 11. The main body case 11 and the upper case 13 may be fixed by being welded to each other, and the main body case 11 and the lower case 17 may be fixed by being welded to each other.

The internal space S1 may be a refrigerant inflow space S1 into which a refrigerant flows, and the refrigerant may flow into the refrigerant inflow space S1 through the refrigerant suction pipe 12 disposed in the main body case 11. The high-low pressure separation plate 90 provided above divides the space into a refrigerant inflow space S1 as a low pressure portion and a refrigerant discharge space S2 as a high pressure portion.

Here, the refrigerant inflow space S1 may correspond to a lower space of the high-and low-pressure separation plate 90, and the refrigerant discharge space S2 may correspond to an upper space of the high-and low-pressure separation plate 90. The upper casing 13 has a discharge pipe 14, and the discharge pipe 14 is connected to the refrigerant discharge space S2 and discharges the refrigerant to the outside. The discharge pipe may be connected to deliver the refrigerant to a condenser (not shown) of the refrigeration cycle.

The driving unit 20 is provided in the refrigerant inflow space S1. The driving unit 20 is used to generate a rotational force to rotate the rotational shaft 30. In the present embodiment, the driving unit 20 is disposed on the lower side relative to the compressing unit 50, but the compressing unit 50 may be disposed on the lower side of the driving unit 20.

The drive unit 20 is substantially composed of a rotor 23 and a stator 21. Here, the rotor 23 and the stator 21 are members that rotate relative to each other, the stator 21 is fixedly provided on the inner peripheral side of the housing 10, and the rotor 23 is rotatably provided inside the stator 21. Here, the stator 21 is composed of a plurality of laminated stator cores and coils wound around the stator cores. In contrast, the stator 21 may be formed of a stator core and a coil wound around the stator core.

On the other hand, the rotor 23 may be provided with a weight 27, whereby the rotor 23 can perform a stable rotational operation even if the rotational shaft 30 has an eccentric portion.

The stator 21 is fixed to an inner wall surface of the housing 10 by heat shrinkage, and a rotation shaft 30 is inserted into a central portion of the rotor 23. The rotary shaft 30 acts to transmit a rotational force to the orbiting scroll 70 of the compression unit 50 when rotating together with the rotor 23. The rotary shaft 30 extends in the vertical direction of the compressor.

The lower end 33 of the rotary shaft 30 is rotatably supported by a lower bearing 19 provided at the lower portion of the housing 10. The lower bearing 19 is supported by a lower frame 18 fixed to an inner surface of the housing 10, and can stably support the rotary shaft 30. The lower frame 18 may be fixed to an inner wall surface of the casing 10 by welding, and a bottom surface of the casing 10 may serve as an oil storage space. The oil stored in the oil storage space can be transferred upward by the rotary shaft 30 or the like, and the oil can enter the compression chambers V1 and V2 of the drive unit 20 and the compression unit 50 and be lubricated.

The upper end portion 34 of the rotating shaft 30 is rotatably supported by a main frame 40. The main frame 40 is fixedly installed on an inner wall surface of the casing 10 like the lower frame 18, and an upper bearing 45 protruding downward is formed on a bottom surface thereof. The upper end 34 of the rotary shaft 30 is inserted into the upper bearing 45, the main frame 40 and the upper bearing 45 are fixed, and the upper end 34 of the rotary shaft 30 and the upper bearing 45 rotate relatively in close contact with each other as the rotary shaft 30 rotates.

In this way, the lower end 33 of the rotating shaft 30 is supported by the lower bearing 19, and the upper end 34 is supported by the upper bearing 45 of the other bearing. Therefore, a first shaft contact surface (see portion a in fig. 7) connected to the lower bearing 19 is formed on the outer surface of the lower end portion 33 of the rotating shaft 30, and a second shaft contact surface (see portion B in fig. 7) connected to the upper bearing 45 is formed on the opposite upper end portion 34. The first shaft contact surface and the second shaft contact surface are each formed with a fine groove D (see fig. 4) by surface treatment. Referring to fig. 2, the contact of the first shaft contact surface with the lower bearing 19 is denoted by reference numeral (r), and the contact of the second shaft contact surface with the upper bearing 45 is denoted by reference numeral (c).

The minute groove portions D are formed on the outer surface of the contact surface, and are formed by spraying fine particles of a metal or a non-metal onto the contact surface. That is, the fine groove portion D is a fine groove shape formed on the contact surface by strongly jetting small particles to the contact surface. The fine grooves D can be formed by spraying Powder (Ceramic Powder) or metal balls (Steel Ball) under high pressure so as to collide with the contact surface.

In the present embodiment, the minute groove portions D are groove shapes having a diameter of 20 μm to 50 μm and a depth of 2 μm to 5 μm. As shown in the enlarged portion of fig. 4, the micro grooves D reduce the contact area of the friction surface to reduce the friction coefficient, and an oil film made of oil may be formed on the edges of the micro grooves D and the inner sides of the micro grooves D by the recessed shape. Fig. 4 shows a state where an oil film is formed inside and around the minute groove portion D. Fig. 7 shows a state where the fixing jig 100 is connected to the rotary shaft 30 for processing the minute groove portions D, and in fig. 7, the contact surface portions of the portions where the minute groove portions D are formed are distinguished by different surface texture representations.

At this time, the first shaft contact surface and the second shaft contact surface may be formed to have different surface-treated areas or different sizes of the minute groove portions D. This is because the external force applied to the first shaft contact surface and the second shaft contact surface may be different during the operation of the compressor, and for example, the area of the fine groove portion D formed in the second shaft contact surface subjected to a large external force and axial load, and the diameter and depth of the fine groove may be larger. Next, a process of adjusting the area or the size of the fine groove D in the surface treatment will be described.

In addition, the compression unit 50 rotates by the rotary shaft 30 in the internal space S1 of the casing 10 to perform a function of compressing the refrigerant, and in the present embodiment, the compression unit 50 is configured by two members that rotate relative to each other, that is, the fixed scroll 60 and the orbiting scroll 70. The orbiting scroll 70 rotates while meshing with the eccentric protrusion 35 protruding from the upper end 34 of the rotary shaft 30, and the volumes of the compression chambers V1 and V2 between the orbiting scroll 70 and the fixed scroll 60 are changed, and in this process, the refrigerant in the compression chambers V1 and V2 is compressed and discharged.

Before the compression unit 50 is described in detail, a coupling structure between the compression unit 50 and the rotary shaft 30 is described, and as shown in fig. 5, a coupling portion 73 is provided on a bottom surface of a orbiting plate 72 of an orbiting scroll 70, and a coupling space 73' is provided inside the coupling portion 73. A slide bush 37 is inserted into the coupling space 73', and an eccentric protrusion 35 of the rotary shaft 30 is inserted into the slide bush 37. The state of these bonds can be seen from fig. 2.

The slide bush 37 moves relative to the eccentric protrusion 35 of the rotary shaft 30 when sliding along a linear path, but moves relative to the swirling scroll 70 when sliding in the circumferential direction. In the following description of the structure, the slide bush 37 has a substantially cylindrical shape, and a slide space 39 penetrating in the vertical direction is formed at the center. The eccentric protrusion 35 is inserted into the sliding space 39 but does not rotate relatively.

That is, the slide bush 37 does not rotate in the state inserted into the eccentric protrusion 35, but can reciprocate along a linear path. For this purpose, a second flat surface portion 39 'is formed on the inner surface of the slide space 39 so as to abut on the first flat surface portion 36 formed on the outer surface of the eccentric protrusion 35, and the second flat surface portion 39' has a D-cut (D-cut) shape. Since the first flat surface portion 36 and the second flat surface portion 39 'are in a state of contact with each other, relative rotation between them can be prevented, and the second flat surface portions 39' are arranged side by side on both side surfaces of the slide space 39.

The outer surface 38a of the slide bush 37 is inserted into the coupling space 73' inside the coupling portion 73 of the swirling coil 70 and causes the swirling coil 70 to perform a swirling motion. In this process, the slide bush 37 can slide in the circumferential direction in the coupling space 73' and perform a relative movement. Unexplained reference numeral 38b is a plane section located on the outer surface of the slide bush 37.

As described above, the slide bush 37, the eccentric protrusion 35, and the coupling portion 73 move relative to each other, and thus a friction surface, i.e., a contact surface is formed. More specifically, (i) a first flat surface portion 36 is formed in the eccentric protrusion 35 of the rotary shaft 30, and this flat surface portion is in surface contact with a second flat surface portion 39' of the inner surface of the sliding space 39 of the sliding bush 37, so that a shaft-bush contact surface having the minute groove portion D is formed in at least one of the first flat surface portion 36 and the second flat surface portion 39', and (ii) a scroll-bush contact surface having the minute groove portion D is also formed in at least one of the inner surface of the coupling space 73' of the coupling portion 73 of the orbiting scroll 70 and the outer surface 38a of the sliding bush 37.

The shaft-liner contact surface and the scroll-liner contact surface are indicated by c in figure 2. As described above, the minute groove portions D are formed also in the shaft-liner contact surface and the scroll-liner contact surface, and the process is the same as that of the first shaft contact surface and the second shaft contact surface described above. That is, the minute groove portions D are formed on the outer surface of the contact surface, and the minute groove portions D are formed by spraying fine particles of a metal or a non-metal onto the contact surface. That is, the fine groove portion D has a fine groove shape formed on the contact surface by strongly jetting small particles toward the contact surface. For reference, in fig. 5, the contact surface portion of the portion where the minute groove portions D are formed is distinguished by different surface texture representations.

Next, the compression unit 50 will be described, in which the fixed scroll 60 and the orbiting scroll 70 rotate in a state of contact with each other, and the orbiting contact surface of the orbiting scroll 70 and the fixed contact surface of the fixed scroll 60 rotate relatively in a state of close contact with each other as described below. Referring to fig. 2, a contact portion when the orbiting contact surface of the orbiting scroll 70 and the fixed contact surface of the fixed scroll 60 rotate in a state of being in close contact with each other is shown by a reference numeral (r). A scroll contact surface is formed in the rotating structure of these scrolls.

First, the fixed scroll 60 will be described, in which the fixed scroll 60 is formed with a fixed plate 62 formed in a disc shape on the upper portion and a fixed scroll portion 65 projecting downward from the fixed plate 62. The fixed scroll 65 may be formed in a spiral shape so as to mesh with a spiral wrap 75 of a spiral scroll 70 described later, and an inlet port for sucking the refrigerant existing in the refrigerant inflow space S1 may be formed in a side surface thereof. A discharge port 67 for discharging the compressed refrigerant may be formed in the center of the fixed scroll 60.

Referring to fig. 6, the inner surface 66 of the fixed scroll 60 may be divided into a plurality of sections, specifically: a first fixing surface 66a which is a side surface of the fixed scroll portion 65; a second fixed surface 66b which is a bottom surface of the fixed scroll 65 and faces the orbiting plate 72 of the orbiting scroll 70; and a third fixing surface 66c which is a bottom surface of the fixing plate 62 and is a portion to which one end of the fixed scroll portion 65 is connected. Among these, the second fixed surface 66b and the third fixed surface 66c facing the orbiting plate 72 are contact surfaces because they rotate relatively in close contact with the orbiting scroll 70. More specifically, the second fixing surface 66b and the third fixing surface 66c become fixing contact surfaces. The fixing contact surface may be surface-treated to form the fine groove D. For reference, in fig. 6, the contact surface portion of the portion where the minute groove portions D are formed is distinguished by different surface texture representations.

In view of the orbiting scroll 70, the orbiting scroll 70 is formed with a substantially disk-shaped orbiting plate 72 and a spiral orbiting scroll 75 protruding from the orbiting plate 72 in the direction of the fixed plate 62. The swirl wrap 75 and the fixed wrap 65 together form compression chambers V1, V2.

The whirl plate 72 of the whirl coil plate 70 performs a whirl motion in a state of being supported on the upper surface of the frame 40, and the cross ring 48 is provided between the whirl plate 72 and the main frame 40 to thereby prevent the whirl coil plate 70 from rotating. Further, a coupling portion 73 into which the eccentric protrusion 35 of the rotary shaft 30 is inserted is formed on the bottom surface of the orbiting plate 72 of the orbiting scroll 70, and the coupling portion 73 protrudes in a substantially ring shape, whereby the rotational force of the rotary shaft 30 can cause the orbiting scroll 70 to orbit. More specifically, the slide bush 37 is located between the eccentric protrusion 35 and the coupling portion 73, which will be described later.

Referring to fig. 6, the inner surface 76 of the swirling coil 70 may be divided into a plurality of sections, specifically: a first orbiting surface 76a which is a side surface of the orbiting scroll 75; a second orbiting surface 76b which is a top surface of the orbiting scroll 75 facing the fixed plate 62 of the fixed scroll 60; and a third spiral surface 76c which is a top surface of the spiral plate 72 and is a portion to which one end of the spiral wrap 75 is connected. The second and third orbiting surfaces 76b and 76c facing the fixed plate 62 are contact surfaces because they are relatively rotated in close contact with the fixed scroll 60. More specifically, the second convolution surface 76b and the third convolution surface 76c become convolution contact surfaces. The convoluted contact surface may be formed with the fine groove portion D by surface treatment. Of course, the minute groove portions D may be formed only in at least a part of the fixed contact surface and the revolving contact surface described above.

In this case, the difference in height between the fixed scroll 60 and the orbiting scroll 70 is preferably within a range of-2 μm to 4 μm in order to prevent operational play and leakage from the compression chambers V1 and V2, which may occur during rotation of the two scrolls. Thus, in the present embodiment, the minute groove portions D formed at the stationary contact surface and the convolute contact surface have a depth of 2 μm to 4 μm.

A back pressure assembly 80 is provided at an upper portion of the compression unit 50. The back pressure unit 80 is provided on the upper side of the fixed plate 62 of the fixed scroll 60, and a substantially annular body forms a skeleton and can be in contact with the fixed scroll 60.

The high-low pressure separation plate 90 described above is formed above the back pressure unit 80, and is separated into the refrigerant inflow space S1 as a low pressure portion and the refrigerant discharge space S2 as a high pressure portion by the high-low pressure separation plate 90. A back pressure hole (not numbered) is formed at the center of the back pressure unit 80, so that the refrigerant can be transferred to the refrigerant discharge space S2 through the high and low pressure separation plate 90.

Next, a method of manufacturing the compressor of the present invention will be described.

First, the utility model discloses a contact surface to the driver part who constitutes the compressor is processed, reduces coefficient of friction, improves the efficiency of compressor from this. Here, the contact surface refers to a contact surface between the rotary shaft 30 and the bearing, a contact surface between the rotary shaft 30 and the compression unit 50, or a contact surface between rotating structures of the compression unit 50.

First, a covering step of covering the periphery of the surface to be processed of the workpiece is performed. Here, the covering is performed to prevent a portion which does not need to be processed or a portion which cannot be processed from being surface-treated by covering a portion other than the processing surface of the member to be processed.

For example, in the case of the rotary shaft 30, the portion other than the lower end portion 33 and the upper end portion 34, that is, the remaining portion other than the portions which become the first shaft contact surface and the second shaft contact surface, may be covered except for a portion a which becomes the lower end portion 33 and a portion B which becomes the upper end portion 34, referring to fig. 7. Alternatively, the first plane part 36, which is in contact with the inner surface of the sliding space 39 of the sliding bush 37, in the outer surface of the eccentric protrusion of the rotating shaft 30 may be excluded from the objects to be covered.

In the case of the compression unit 50, the top surface of the orbiting scroll 75 constituting the orbiting scroll 70 and the bottom surface 66c of the fixed scroll 65 which is in close contact with the top surface 76b of the orbiting scroll 75 and constitutes the fixed scroll 60 are surface-treated, and thus the rest is covered. That is, in the covering step, the side surface of the orbiting wrap 75 and the side surface of the fixed wrap 65 are covered, and only the top surface 76b of the orbiting wrap 75 and the bottom surface 66c of the fixed wrap 65 facing in the direction of the rotation shaft 30 are exposed for surface treatment.

Thereafter, a fixing step of fixing the workpiece is continued, in which one side of the rotating shaft 30 is fixed by the fixing jig 100, as shown in fig. 7. The clamp body 101 of the fixing clamp 100 is protruded with a rotating bar 105 for rotation, and the rotating bar can be grasped to rotate the workpiece. In the case of the compression unit 50, the clamp may be combined with the outer surface of the orbiting plate 72 of the orbiting scroll 70 and the outer surface of the fixed plate 62 of the fixed scroll 60.

In this state, a blasting step of blasting fine particles onto the surface to be processed, which is the contact surface, while rotating the member to be processed is performed. The rotation of the workpiece may be performed by rotating a rotating jig, which may be rotated by manual work of an operator, or may be fixed to an additional device.

The spraying of fine particles may be considered as a spraying process, and for example, a method of spraying sand or metal balls onto a surface at a high speed by using compressed air or the like may be used. According to the kind of the particles used in such blasting, sand blasting and shot blasting are possible, and in the present embodiment, the fine groove portions D are formed by blasting metal balls having a diameter of about 100 μm.

The micro groove portion D manufactured as described above reduces the friction coefficient of the member, and the size of the micro groove portion D may be varied depending on the condition of the contact surface. For example, the friction coefficient can be further reduced by increasing the number of the fine groove portions D in the contact surface having a large friction force, and since the fine groove portions D are formed by spraying fine particles, the size of the fine particles can be changed to obtain the fine groove portions D meeting the conditions of the contact surface and the friction coefficient corresponding thereto.

In particular, by rotating the member with the fixing jig 100 and spraying fine particles, the fine groove portions D can be uniformly formed on the work surface, and the density of the fine groove portions D can be changed by adjusting the rotation speed. That is, since the friction coefficient of the compressor member can be set by adjusting the rotation speed of the fixing jig 100, various conditions of the compressor can be satisfied.

Thereby, the fine groove portion D having a groove shape with a diameter of 20 μm to 50 μm and a depth of 2 μm to 5 μm is formed. The micro groove D may have a concave shape, so that an oil film formed of oil may be formed on the edge of the micro groove D and the inside of the micro groove D. Fig. 9 shows a comparison of the outer surface (right photograph) of the rotating shaft 30 on which the sipe portion D is formed as described above and an unprocessed outer surface (left photograph).

In this case, if the diameter of the fine groove D is less than 20 μm, the effect of reducing the friction coefficient is low, and it is difficult to expect improvement of the compression efficiency, and if it is 50 μm or more, the friction coefficient may be increased or the oil film may be decreased instead. From the viewpoint of the efficiency of the compressor in which the minute groove portions D are processed, under the condition that the surface groove width of the minute groove portions D is 20 to 50 μm and the depth is 3 to 5 μm, the input value is decreased by 0.5 to 0.6%, and thus the efficiency of the compressor is improved by 0.4 to 0.6%. The reduction in lift efficiency produced under other conditions than this was less than 0.3%.

While the above description describes that all the constituent elements constituting the embodiments of the present invention are combined together or operated in combination, the present invention is not necessarily limited to the above embodiments, and all the constituent elements may be selectively combined to operate in more than one manner within the scope of the objects of the present invention. In addition, in terms of the above-described terms such as "including", "constituting" or "having", unless otherwise specified, it means that the constituent element can be internally carried, and therefore it should be construed that other constituent elements may be included without excluding other constituent elements. Unless otherwise defined, technical or scientific terms are to be construed as meaning commonly understood by one of ordinary skill in the art. Terms commonly used as terms defined in dictionaries should be interpreted as being consistent with the meaning of the context unless explicitly defined in the present invention, and should not be interpreted as being excessively generalized or excessively reduced.

The above description is only for exemplifying the technical idea of the present invention, and those skilled in the art can make various modifications and variations without departing from the scope of the essential features of the present invention. Therefore, the embodiments and drawings disclosed in the present invention are not intended to limit the technical idea of the present invention, but to illustrate, and the technical idea of the present invention is not limited to such embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope of equivalents thereof are included in the scope of protection of the present invention.

Claims

1. A compressor, comprising:

a casing, a refrigerant suction pipe for sucking the refrigerant connected with the inner space;

a rotating shaft which is rotated by a driving unit and is rotatably supported in the inner space by a bearing; and

a compression unit rotated in the inner space of the casing by the rotation shaft to compress a refrigerant,

at least a part of a contact surface between the rotary shaft and the bearing, a contact surface between the rotary shaft and the compression unit, and a contact surface between rotary structures of the compression unit is formed with a fine groove portion formed by surface treatment.

2. The compressor of claim 1,

the surface treatment is performed by spraying fine particles of a metal or a non-metal onto the contact surface, and the fine groove portions are uniformly distributed on the contact surface.

3. The compressor of claim 1,

the rotary shaft has a first shaft contact surface on one side connected to the bearing and a second shaft contact surface on the opposite side rotatably connected to the compression unit or another bearing, and the first shaft contact surface and the second shaft contact surface have respective minute groove portions.

4. The compressor of claim 3,

in the first shaft contact surface and the second shaft contact surface, areas in which the minute groove portions are distributed are different from each other, or sizes of the minute groove portions are different from each other.

5. The compressor of claim 1,

the minute groove portion is formed in a groove shape having a diameter of 20 to 50 μm and a depth of 2 to 5 μm, and an oil film formed of oil is formed at an edge of the minute groove portion and an inner side of the minute groove portion.

6. The compressor of claim 1,

the compression unit includes: a fixed scroll fixedly disposed in the inner space; and a swirl disk connected to the rotary shaft and performing a swirling motion, and forming a compression chamber between the fixed scroll and the swirl disk by engaging with the fixed scroll,

at least a part of a top surface of a spiral wrap portion constituting the spiral wrap and a bottom surface of a fixed wrap portion constituting the fixed wrap, which is in close contact with the top surface of the spiral wrap portion, is a spiral contact surface having a fine groove portion formed on a surface thereof.

7. The compressor of claim 6,

a sliding bush is coupled between the rotating shaft and a coupling portion of the swirling scroll constituting the compression unit, and a shaft-bush contact surface having a fine groove portion is formed on at least one of an outer surface of the rotating shaft and an inner surface of the sliding bush.

8. The compressor of claim 7,

an eccentric protrusion protruding toward an upper end portion of the rotary shaft is inserted into a sliding space of the slide bush, a second flat surface portion abutting against a first flat surface portion located on an outer surface of the eccentric protrusion is formed on an inner surface of the sliding space, and at least one of the first flat surface portion and the second flat surface portion is a shaft-bush contact surface on which a fine groove portion is formed.

9. The compressor of claim 7,

at least one of an outer surface of the slide bush and an inner surface of a coupling portion of the orbiting scroll into which the slide bush is inserted is a scroll-bush contact surface having a minute groove portion formed on a surface thereof.