Scroll compressor and method for manufacturing scroll for scroll compressor

Abstract

The present invention relates to a scroll compressor comprising: an orbiting scroll carrying out an orbiting motion; and a fixed scroll engaged with and coupled to the orbiting scroll and forming a compression chamber along with the orbiting scroll. At least one of the orbiting scroll and the fixed scroll may comprise: a wrap portion configuring an orbiting wrap of the orbiting scroll or a fixed wrap of the fixed scroll; and a frame portion which is coupled to one end portion of the wrap portion and configures an orbiting end plate of the orbiting scroll or a fixed end plate of the fixed scroll. The frame portion may be formed of a material having a lower strength than the wrap portion. In addition, the present invention also provides a method for manufacturing a scroll for the scroll compressor. According to the present invention, processing steps for obtaining the final dimensions of the scroll can be minimized, thereby reducing manufacturing costs and improving productivity.

Description

Method for manufacturing a scroll compressor and a scroll for a scroll compressor

[0001] The present invention relates to a scroll compressor and a method for manufacturing a scroll for a scroll compressor.

[0002] A scroll compressor consists of a pair of compression chambers formed by the interlocking of a rotating scroll and a stationary scroll (or non-rotating scroll) that constitute the compression section. Since suction, compression, and discharge occur continuously while the rotating scroll is rotating, this type of scroll compressor has a small number of parts and enables high-speed rotation. Furthermore, noise and vibration are low because there is minimal fluctuation in the torque required for compression and suction and compression occur continuously. For these reasons, scroll compressors are widely applied in air conditioners.

[0003] In such scroll compressors, the rotating scroll and the stationary scroll (hereinafter collectively referred to as scrolls) are generally formed by casting an iron-based material such as cast iron.

[0004] In such scrolls, the scroll wrap, which performs direct compression in conjunction with the relative scroll's scroll wrap, not only has a very complex spiral shape, but the shape and dimensions of the scroll wrap must also be very precise to properly perform the compression.

[0005] Due to the nature of casting, formed castings exhibit large dimensional errors. Therefore, the current practice involves producing scroll castings with approximate shapes and dimensions through casting, and then achieving the precision required for scrolls by performing multiple machining processes, such as rough cutting and precision cutting, on them.

[0006] In particular, for scroll laps with helical cross-sections, machining is extremely difficult due to their complex geometry. Consequently, the process of machining scroll laps results in the most severe tool wear and requires a very long processing time.

[0007] Despite the excellent performance characteristics of scroll compressors, such as high compression efficiency and low noise, the difficulty of processing during the scroll manufacturing process increases the manufacturing cost of the scroll and consequently acts as a major factor in raising the price of scroll compressors containing the scroll.

[0008] Meanwhile, scrolls manufactured from heterogeneous materials have recently been proposed for the sake of weight reduction. The difficulty of processing these heterogeneous material scrolls also significantly impacts manufacturing costs.

[0009] Korean Published Patent No. 2020-0140068 (hereinafter referred to as "Patent Document 1") discloses a scroll compressor in which the part forming the friction surface of a fixed scroll or a rotary scroll is formed from cast iron, and the part not forming the friction surface is formed from plastic. This allows for the achievement of lightweighting of the scroll and the scroll compressor including such a scroll. However, in the scroll of Patent Document 1, the part forming the friction surface, namely the scroll wrap, is formed from cast iron, that is, by casting. Considering that the processing difficulty of the scroll wrap is the highest, the effect of reducing manufacturing costs is not significant with Patent Document 1, which requires forming the scroll wrap by performing multiple stages of machining even though a part is formed from plastic, which has a lower processing difficulty.

[0010] The objective of the present invention is to provide a scroll compressor comprising a scroll configured to achieve the required dimensional accuracy through minimal processing.

[0011] Another objective of the present invention is to provide a scroll compressor comprising a scroll configured to reduce manufacturing costs by minimizing processing steps.

[0012] Another objective of the present invention is to provide a scroll compressor comprising a scroll configured to reduce weight by combining heterogeneous materials.

[0013] Another objective of the present invention is to provide a scroll compressor comprising a scroll configured to improve the bonding strength between components formed from heterogeneous materials of the scroll.

[0014] Another objective of the present invention is to provide a method for manufacturing a scroll for a scroll compressor as described above.

[0015] To achieve the objective of the present invention, a scroll compressor may be provided comprising: a rotating scroll that performs a rotating motion; and a fixed scroll that is engaged with and coupled to the rotating scroll to form a compression chamber together with the rotating scroll. At least one of the rotating scroll and the fixed scroll may include a wrap portion constituting a rotating wrap of the rotating scroll or a fixed wrap of the fixed scroll; and a frame portion coupled to one end of the wrap portion to constituting a rotating end plate of the rotating scroll or a fixed end plate of the fixed scroll. The frame portion may be made of a material having lower strength than the wrap portion.

[0016] According to this, by forming the frame portion with a material having lower strength than the wrap portion, the difficulty of processing is reduced, thereby allowing the number of processing steps required to obtain the final dimensions of the scroll to be reduced. In addition, by using different materials for the wrap portion and the frame portion, the weight of the scroll and the scroll compressor containing it can be reduced.

[0017] For example, the above-mentioned wrap portion may have an uneven space formed in the part in contact with the above-mentioned frame portion so that a part of the frame portion penetrates.

[0018] As a result, the wrap and frame sections, made of different materials, can be more firmly joined.

[0019] The above-mentioned uneven space may have a pattern that is irregularly formed or regularly formed.

[0020] If the pattern of the uneven space is formed irregularly, the bonding strength between the wrap part and the frame part can be further improved, and if the pattern of the uneven space is formed regularly, the work of forming the uneven space can be easier.

[0021] For example, the above frame part may be made of a resin material.

[0022] The resin material forming the frame can have higher dimensional accuracy and be easier to process during molding compared to the material with higher strength of the wrap portion. Accordingly, the final dimensions of the frame can be obtained without processing or with minimal processing, thereby reducing manufacturing costs.

[0023] For example, the frame portion may have an insertion groove into which one end of the wrap portion is inserted on a surface that is coupled to one end of the wrap portion.

[0024] According to this, the contact area between the wrap portion and the frame portion is increased, thereby improving the bonding strength between the wrap portion and the frame portion.

[0025] In addition, to achieve the objective of the present invention, a method for manufacturing a scroll for a scroll compressor may be provided. The method for manufacturing a scroll for a scroll compressor may include the step of forming a wrap portion constituting a swivel wrap of a swivel scroll or a fixed wrap of a fixed scroll; and the step of forming a frame portion constituting a swivel end plate of the swivel scroll or a fixed end plate of the fixed scroll. The wrap portion may have dimensions identical to the final dimensions of the swivel wrap or the fixed wrap, or may have increased dimensions that can be processed to the final dimensions through a single machining process. The frame portion may be made of a material having lower strength than the wrap portion.

[0026] According to this, the final dimensions of the wrap portion can be obtained by not machining the wrap portion or by performing only a single machining step, thereby achieving dimensional accuracy with minimal machining. As the machining steps can be minimized in this way, the manufacturing cost of the scroll and the scroll compressor containing it can be lowered and productivity increased. Furthermore, by molding the frame portion using a resin material with low machining difficulty, the manufacturing cost of the scroll and the scroll compressor containing it can also be lowered and productivity increased.

[0027] For example, a method for manufacturing a scroll for a scroll compressor may further include, after the step of forming the wrap portion, a step of forming an uneven space such that a part of the frame portion penetrates into the portion where the wrap portion contacts the frame portion.

[0028] As a result, the wrap part and the frame part, which are made of different materials, can be more firmly joined. The above-mentioned uneven space can be formed by sandblasting, etching, cutting, or laser processing.

[0029] For example, the frame portion can be molded by insert injection molding at one end of the wrap portion.

[0030] According to this, by insert-molding the frame part, the final dimensions of the swivel end plate of a swivel scroll or the fixed end plate of a fixed scroll can be obtained simply and easily with minimal processing. Accordingly, productivity can be increased and the rise in manufacturing costs can be suppressed.

[0031] For example, the above-mentioned wrap portion can be formed by sintering iron-based material powder.

[0032] By sintering and molding the wrap portion, the dimensional accuracy of the wrap portion can be improved. In addition, a portion of the frame portion can penetrate into the pores naturally formed by sintering, thereby improving the bonding strength between the wrap portion and the frame portion.

[0033] For example, a method for manufacturing a scroll for a scroll compressor may further include a step of removing the increased dimensions of the wrap portion to obtain the final dimensions of the wrap portion after the step of forming the wrap portion and before the step of forming the frame portion.

[0034] If the increased dimensions of the wrap portion are removed after forming the wrap portion and before forming the frame portion, the processing of the area where the wrap portion and the frame portion meet can be facilitated.

[0035] As another example, in a method for manufacturing a scroll for a scroll compressor, the frame portion may have increased dimensions that can be processed to the final dimensions of the swivel plate or fixed plate through a single machining process. In this case, the method for manufacturing a scroll for a scroll compressor may further include, after the step of forming the frame portion, a step of removing the increased dimensions of the wrap portion and the increased dimensions of the frame to obtain the final dimensions of the swivel scroll or the fixed scroll.

[0036] Since the increased dimensions of the wrap and frame sections can be machined to the final dimensions through a single machining process, the machining steps of the scroll can be minimized, thereby lowering the manufacturing cost of the scroll and the scroll compressor containing it and increasing productivity.

[0037] In addition, to achieve the objective of the present invention, a method for manufacturing a scroll for a scroll compressor may be provided. The method for manufacturing a scroll for a scroll compressor may include: a step of forming a wrap portion constituting a swivel wrap of a swivel scroll or a fixed wrap of a fixed scroll by sintering a powder of an iron-based material; a step of forming a frame portion constituting a swivel end plate of the swivel scroll or a fixed end plate of the fixed scroll by insert injection of a resin material into the wrap portion; and a step of obtaining the final dimensions of the swivel scroll or the fixed scroll by processing the wrap portion and the frame portion. Prior to the step of obtaining the final dimensions, either or both of the wrap portion and the frame portion may have increased dimensions such that the final dimensions can be obtained through a single machining process.

[0038] Dimensional accuracy can be increased by sintering and molding the wrap portion and insert-injecting the frame portion, and since the final dimensions can be obtained through a single machining process, the dimensional accuracy required for a swivel scroll or a fixed scroll can be achieved with minimal machining.

[0039] According to the present invention, dimensional accuracy can be increased by sintering and molding the wrap portion and insert-injecting the frame portion, and since the final dimensions can be obtained through a single machining process, the dimensional accuracy required for a rotating scroll or a fixed scroll can be achieved with minimal machining.

[0040] In addition, by minimizing the processing steps in this way, the manufacturing cost of the slewing scroll and / or fixed scroll and the scroll compressor including them can also be reduced.

[0041] In addition, according to the present invention, the weight of a rotating scroll and / or a fixed scroll and a scroll compressor including the same can be reduced by molding the wrap portion and the frame portion from different materials.

[0042] In addition, according to the present invention, by forming an uneven space so that a part of the frame penetrates the wrap portion, the bonding strength between the wrap portion and the frame, which are molded from different materials, can be improved.

[0043] FIG. 1 is a longitudinal cross-sectional view illustrating the interior of a scroll compressor according to one embodiment of the present invention.

[0044] FIG. 2 is a perspective view illustrating a rotating scroll of a scroll compressor according to one embodiment of the present invention.

[0045] FIG. 3 is an exploded perspective view illustrating the rotating scroll of FIG. 2.

[0046] FIG. 4 is a perspective view showing the joint portion of the wrap portion and the frame portion by cutting the rotating scroll of FIG. 2.

[0047] FIG. 5a is a cross-sectional view showing an uneven space provided in the form of pores on the surface of the wrap portion as an example illustrating an enlarged view of portion A of FIG. 3.

[0048] FIG. 5b is a cross-sectional view showing an uneven space provided on the surface of the wrap portion as another example illustrating a magnified view of portion A of FIG. 3.

[0049] FIG. 6 is a perspective view illustrating a fixed scroll of a scroll compressor according to one embodiment of the present invention.

[0050] FIG. 7 is a flowchart illustrating a method for manufacturing a scroll according to an embodiment of the present invention.

[0051] FIG. 8 is an exploded perspective view showing the mold and the rotating scroll in cut to show the configuration of the mold for manufacturing the rotating scroll of FIG. 2 and the rotating scroll being insert-molded within the mold.

[0052] FIG. 9 is a cross-sectional view showing an enlarged view of section B of FIG. 4.

[0053] Hereinafter, a scroll compressor and a method for manufacturing a scroll for a scroll compressor according to the present invention will be described in detail based on an embodiment illustrated in the attached drawings.

[0054] For reference, the scroll compressor according to the present invention is a bottom-compression scroll compressor in which the compression section is located below the electric motor (drive motor) and the rotation axis overlaps on the same plane as the slewing wrap. This type of scroll compressor is known to be suitable for application in refrigeration cycles under high temperature and high compression ratio conditions.

[0055] In addition, in the following description, directions such as up, down, left, and right are explained based on the scroll compressor shown in FIG. 1. For example, in FIG. 1, the motor and the compression unit are arranged in the up and down direction, and it can be understood that the motor is arranged above the compression unit.

[0056] FIG. 1 is a cross-sectional view illustrating the interior of a scroll compressor according to one embodiment of the present invention.

[0057] Referring to FIG. 1, a bottom-compression scroll compressor (1) according to one embodiment of the present invention may have a drive unit (20) that generates rotational force and forms a drive motor installed on the upper side of the inside of a casing (10), and a compression unit (30) that compresses a refrigerant by receiving the rotational force of the drive unit (20) and having a predetermined space (intermediate space) (10a) installed on the lower side of the drive unit (20).

[0058] The casing (10) may be composed of a cylindrical shell (11) and an upper shell (12) and a lower shell (13) that cover the upper and lower parts of the cylindrical shell (11), respectively, to form a sealed container together with the cylindrical shell (11). The lower shell (13) may also form a lower space (10c), which is a storage space, together with the cylindrical shell (11).

[0059] A refrigerant suction pipe (15) can be installed through the side of the cylindrical shell (11) to be directly connected to the suction chamber of the compression section (30), and a refrigerant discharge pipe (16) can be installed on the upper part of the upper shell (12) to be connected to the upper space (10b) of the casing (10).

[0060] The refrigerant discharge pipe (16) is a passage for discharging compressed refrigerant discharged from the compression section (30) to the upper space (10b) of the casing (10) to the outside. The refrigerant discharge pipe (16) is extended so as to be inserted into the middle of the upper space (10b) of the casing (10). By doing so, the upper space (10b) of the casing (10) can form a kind of oil separation space for separating oil mixed in the refrigerant. In some cases, a separate oil separator (not shown) for separating oil mixed in the refrigerant may be connected to the refrigerant discharge pipe (16) inside the casing (10) including the upper space (10b) or within the upper space (10b).

[0061] The electric motor (20) consists of a stator (21) and a rotor (22) that rotates inside the stator (21). The stator (21) is provided with teeth and slots forming a plurality of coil winding sections (not shown) along the circumferential direction on its inner surface, and coils (25) are wound on these teeth and slots.

[0062] A frame (31) forming a compression section (30) can be fixedly coupled to the inner surface of the casing (10) at a predetermined interval on the lower side of the stator (21). The frame (31) can be fixedly coupled to the casing (10) by shrink-fitting or welding the outer surface of the frame (31) to the inner surface of the cylindrical shell (11). An annular frame side wall section (311) can be formed on the edge of the frame (31).

[0063] A first bearing portion (312) may be formed at the center of the frame (31), having a first bearing hole (312a) formed through in the axial direction. The main bearing portion (51) of the rotation shaft (50), which will be described later, is rotatably inserted into the first bearing hole (312a) of the first bearing portion (312) and supported in the radial direction.

[0064] A fixed scroll (32) may be installed on the lower surface of the frame (31) with a pivoting scroll (33) eccentrically coupled to a rotation axis (50) described later in between. The fixed scroll (32) may be fixedly coupled to the frame (31), but may also be coupled so as to be movable in the axial direction.

[0065] The fixed scroll (32) may have a fixed plate (321) formed in a roughly circular shape, and a scroll side wall (322) formed at the edge of the fixed plate (321) that is coupled to the lower edge of the frame (31).

[0066] On the upper surface of the fixed plate (321), a fixed wrap (323) may be formed to form a compression chamber (Vc) by engaging with the rotating wrap (332) of the rotating scroll (33) to be described later.

[0067] A second bearing portion (326) having a second bearing hole (326a) may be formed at the center of the fixed plate (321). The sub-bearing portion (52) of the rotating shaft (50), which will be described later, is rotatably inserted into the second bearing hole (326a) of the second bearing portion (326) and supported in the radial direction.

[0068] A suction port (324) is formed through one side of the scroll side wall (322) to communicate with the refrigerant suction pipe (15) and the suction chamber, and a discharge port (325) for discharging compressed refrigerant can be formed in the central part of the fixed end plate (321) to communicate with the discharge chamber.

[0069] Additionally, a discharge cover (34) may be attached to the lower side of the fixed scroll (32) to guide the refrigerant discharged from the compression chamber (Vc) to the first refrigerant passage (PG1) to be described later. The discharge cover (34) may be formed such that its internal space accommodates the discharge port (325), and at the same time accommodates the inlet of the first refrigerant passage (PG1) which guides the refrigerant discharged from the compression chamber (Vc) through the discharge port (325) to the upper space (10b) of the casing (10), more precisely, to the space between the electric motor (20) and the compression unit (30).

[0070] The rotating scroll (33) can be installed to rotate between the frame (31) and the fixed scroll (32).

[0071] The rotating scroll (33) may have a rotating plate (331) formed in a roughly circular shape. On the lower surface of the rotating plate (331), a rotating wrap (332) may be formed to form a compression chamber (Vc) by engaging with a fixed wrap (323).

[0072] The pivot wrap (332) can be formed spirally together with the fixed wrap (323). However, it is not necessarily limited to this and can be formed in various other shapes. For example, the pivot wrap (332) may have a shape formed by connecting multiple arcs with different diameters and origins, and the outermost curve may be formed in a roughly elliptical shape having a major axis and a minor axis. The fixed wrap (323) may also be formed in the same way.

[0073] In the central part of the pivot plate (331), a pivot shaft coupling part (333) may be formed through in the axial direction, which forms the inner end of the pivot wrap (332) and into which the eccentric part (53) of the pivot shaft (50) to be described later is rotatably inserted and coupled.

[0074] The outer periphery of the rotational shaft coupling part (333) is connected to the pivoting wrap (332) to form a compression chamber (Vc) together with the fixed wrap (323) during the compression process. In the following description, the rotational shaft coupling part (333) may be collectively referred to as the pivoting wrap (332) together with the pivoting wrap (332).

[0075] The compression chamber (Vc) is formed between the fixed end plate (321) and the fixed wrap (323) of the fixed scroll (32), and between the rotating wrap (332) and the rotating end plate (331) of the rotating scroll (33). This compression chamber (Vc) can be formed by continuously forming a suction chamber, an intermediate pressure chamber, and a discharge chamber along the direction of travel of the fixed wrap (323) and the rotating wrap (332).

[0076] The fixed scroll (32) and the rotating scroll (33) forming these compression chambers are manufactured by insert injection molding a frame part (328, 338) made of resin material onto a wrap part (327, 337) made of metal material, which will be explained in detail later.

[0077] An Oldham ring (35) that prevents rotation of the rotating scroll (33) is installed between the upper surface of the rotating scroll (33) and the lower surface of the corresponding frame (31), and a sealing member (36) may be installed inside the Oldham ring (35).

[0078] Meanwhile, a flow separation unit (40) is installed in an intermediate space (10a), which is a transit space formed between the lower surface of the electric motor (20) and the upper surface of the compression unit (30). By means of the flow separation unit (40), the refrigerant discharged from the compression unit (30) can be prevented from meeting and mixing with oil moving from the upper space (10b) of the electric motor (20), which is an oil separation space, to the lower space (10c) of the compression unit (30), which is a low-oil space.

[0079] Meanwhile, the upper part of the rotating shaft (50) is pressed into the center of the rotor (22) and coupled, while the lower part is coupled to the compression part (30) and can be supported radially. By this, the rotating shaft (50) transmits the rotational force of the electric motor (20) to the pivoting scroll (33) of the compression part (30). Then, the pivoting scroll (33), which is eccentrically coupled to the rotating shaft (50), performs a pivoting motion relative to the fixed scroll (32).

[0080] A main bearing portion (51) may be formed in the lower half of the rotating shaft (50) to be inserted into the first bearing hole (312a) of the frame (31) and supported in the radial direction, and a sub-bearing portion (52) may be formed on the lower side of the main bearing portion (51) to be inserted into the second bearing hole (326a) of the fixed scroll (32) and supported in the radial direction. An eccentric portion (53) may be formed between the main bearing portion (51) and the sub-bearing portion (52) to be inserted into and coupled to the rotating shaft coupling portion (333).

[0081] The main bearing portion (51) and the sub-bearing portion (52) are formed on a coaxial line to have the same axial center, and the eccentric portion (53) may be formed radially eccentrically with respect to the main bearing portion (51) or the sub-bearing portion (52). The sub-bearing portion (52) may also be formed eccentrically with respect to the main bearing portion (51).

[0082] An oil supply channel (50a) for supplying oil to the main bearing section (51), sub-bearing section (52), and eccentric section (53) may be formed along the axial direction inside the rotating shaft (50). As the compression section (30) is located lower than the transmission section (20), the oil supply channel (50a) may be formed by a groove from the bottom of the rotating shaft (50) to a position higher than the bottom or middle height of the stator (21) or the top of the main bearing section (51). Of course, in some cases, the oil supply channel (50a) may be formed by penetrating the rotating shaft (50) in the axial direction.

[0083] An oil feeder (60) for pumping oil filled in the lower space (10c) may be attached to the lower end of the rotating shaft (50), that is, the lower end of the sub-bearing part (52). The oil feeder (60) may consist of an oil supply pipe (61) that is inserted into and connected to the oil supply passage (50a) of the rotating shaft (50), and a blocking member (62) that accommodates the oil supply pipe (61) to block the intrusion of foreign matter. The oil supply pipe (61) may be positioned to pass through the discharge cover (34) and be submerged in the oil of the lower space (10c).

[0084] The refrigerant passage includes a first refrigerant passage (PG1) and a second refrigerant passage (PG2). The first refrigerant passage (PG1) can be formed by sequentially penetrating the scroll side wall portion (322) of the fixed scroll (32) and the frame side wall portion (311) of the frame (31) from the inside of the passage separation unit (40), that is, from the direction of the rotation axis (50) which is inside relative to the passage separation unit (40). The second refrigerant passage (PG2) is formed by the gap between the inner surface of the stator (21) of the electric motor (20) and the outer surface of the rotor (22), and the coil winding portion.

[0085] The refrigerant discharged into the intermediate space (10a) between the motor unit (20) and the compression unit (30) through the first refrigerant path (PG1) moves to the upper space (10b) formed on the upper side of the motor unit (20) through the second refrigerant path (PG2) formed in the motor unit (20).

[0086] The oil passage includes a first oil passage (PO1) passing through the electric motor (20) and a second oil passage (PO2) passing through the compression part (30). The first oil passage (PO1) may be formed by a plurality of D-cut surfaces (21a) formed along the circumferential direction on the outer surface of the stator (21) and by the D-cut surfaces (21a) and the inner surface of the cylindrical shell (11).

[0087] The second oil passage (PO2) can be formed by sequentially penetrating a plurality of communication grooves formed along the circumferential direction on the outer surface of the frame side wall portion (311) of the frame (31) from the outside of the passage separation unit (40) and a plurality of communication grooves formed on the outer surface of the scroll side wall portion (322) of the fixed scroll (32).

[0088] Accordingly, the oil separated from the refrigerant in the upper space (10b) moves to the lower space (10c) through the first oil passage (PO1) and the second oil passage (PO2).

[0089] The unexplained symbol 70 in the drawing is an accumulator.

[0090] The lower compression type scroll compressor (1) according to one embodiment of the present invention as described above operates as follows.

[0091] When power is applied to the electric motor (20), rotational force is generated in the rotor (22) and the rotating shaft (50), causing them to rotate. As the rotating shaft (50) rotates, the swivel scroll (33), which is eccentrically coupled to the rotating shaft (50), rotates by means of the Oldham ring (35).

[0092] Then, the refrigerant supplied from the outside of the casing (10) through the refrigerant suction pipe (15) flows into the compression chamber (Vc), and as the volume of the compression chamber (Vc) decreases due to the rotational movement of the rotational scroll (33), the refrigerant is compressed and discharged into the internal space of the discharge cover (34) through the discharge port (325).

[0093] The refrigerant discharged into the internal space of the discharge cover (34) moves to the upper space (10b) of the electric motor (20) via the first refrigerant path (PG1) and the second refrigerant path (PG2). The refrigerant that has moved to the upper space (10b) of the electric motor (20) is discharged to the outside of the casing (10) through the refrigerant discharge pipe (16).

[0094] Additionally, the oil mixed with the refrigerant in the upper space (10b) of the electric motor (20) is separated from the refrigerant. The oil separated from the refrigerant is recovered into the lower space (10c), which is the oil storage space of the casing (10), through the first oil passage (PO1) between the inner surface of the casing (10) and the stator (21) and the second oil passage (PO2) between the inner surface of the casing (10) and the outer surface of the compression part (30).

[0095] In a scroll compressor (1) having such a configuration, the rotating scroll (33) and fixed scroll (32) forming the compression chamber (Vc) have a complex shape of the scroll wrap (i.e., rotating wrap (332) and fixed wrap (323)) formed spirally, and in order to properly perform compression work with such a complex shape, the shape and dimensions of the scroll, especially the scroll wrap, must be precise.

[0096] However, when forming a scroll through casting as in the conventional method, due to the characteristics of casting, the cast scroll casting has a significant dimensional error compared to the final dimensions, for example, a dimensional error of at least 300 μm, and it is extremely difficult to eliminate such dimensional error in a single processing step.

[0097] Accordingly, conventionally, as explained above, scrolls having a final shape and final dimensions are manufactured by processing a scroll casting, which is formed into an approximate shape by casting, through several stages.

[0098] Accordingly, the present embodiment discloses a method for manufacturing a scroll by forming only the wrap portion of the scroll using a metal material, for example, an iron-based material powder, preferably by sintering, and insert-molding the frame portion of the scroll, i.e., the remaining portion excluding the wrap portion. By doing so, manufacturing costs can be lowered and productivity increased by minimizing the processing steps required to obtain the final dimensions and final shape of the scroll.

[0099] FIG. 2 is a perspective view illustrating a rotating scroll (33) of a scroll compressor (1) according to an embodiment of the present invention. FIG. 3 illustrates the wrap portion (337) and frame portion (338) of the rotating scroll of FIG. 2 in disassembled form. FIG. 4 is a perspective view showing the combined portion of the wrap portion (337) and frame portion (338) by cutting the rotating scroll (33) of FIG. 2.

[0100] The rotating scroll (33) of the scroll compressor (1) according to one embodiment of the present invention may be composed of two parts formed from different materials, namely a wrap part (337) and a frame part (338).

[0101] The wrap portion (337) is a part that constitutes the pivot wrap (332) of the pivot scroll (33). As shown in FIG. 3, the wrap portion (337) has a circular pivot shaft coupling portion (333) formed in the center and a cross-section that extends from one side of the pivot shaft coupling portion (333) and spirally wound toward the edge, and the inner pivot wrap (332) and the adjacent outer pivot wrap (332) are spaced apart at a predetermined interval. As previously mentioned, the pivot wrap (332) can be used in the concept of including the pivot shaft coupling portion (333) together with the pivot wrap (332).

[0102] Additionally, the spiral cross-sectional shape of the wrap portion (337) extends in a straight line from one end (rotating plate side end) (337a) which is coupled to the frame portion (338) (rotating plate (331)) in the axial direction to the other end (fixed plate side end) (337b) which contacts the fixed plate (321) of the fixed scroll (32).

[0103] The rotating end (337a) of the wrap portion (337) is blocked by the frame portion (338) described later, and the fixed end (337b) of the wrap portion (337) is in contact with one side of the fixed end (321) of the fixed scroll (32).

[0104] These wrap portions (337) may be made of a metal material, preferably an iron-based material.

[0105] In one embodiment, the lap portion (337) may be formed by sintering a powder of an iron-based material. The sintering referred to herein may include not only sintering molding in the traditional sense, which involves forming by pressing, but also metal injection molding (MIM) performed by adding an organic binder to metal powder. In another embodiment, the lap portion (337) may be formed by precision forging, precision casting, or precision die casting of an iron-based material.

[0106] The wrap portion (337) may have uneven spaces (3371, 3372) on its surface as shown in FIG. 5a and FIG. 5b.

[0107] The bonding strength between the wrap portion (337) and the frame portion (338) can be improved by the resin material of the frame portion (338) described later penetrating into the uneven spaces (3371, 3372) of the wrap portion (337) as shown in FIG. 9.

[0108] In an example where the wrap portion (337) is formed by sintering, pores, i.e., uneven spaces (3371), are naturally formed on the surface of the wrap portion (337) depending on the characteristics of the sintering (Fig. 5a). In an example where the wrap portion (337) is formed by precision forging, precision casting, or precision die casting, unlike in the case of sintering, the wrap portion (337) does not contain pores. Accordingly, as described below, uneven spaces (3372) to improve the bonding strength between the wrap portion (337) and the frame portion (338) can be formed by processing the surface of the wrap portion (337) (Fig. 5b). The uneven spaces (3372) can be formed, for example, by sandblasting, etching, cutting, or laser processing.

[0109] The frame portion (338) constitutes the remaining part of the rotating scroll (33) excluding the wrap portion (337). In the example of the rotating scroll (33) shown in FIGS. 2 to 4, the frame portion (338) may constitute a rotating plate (331).

[0110] The frame part (338) may be made of a resin material, for example, a plastic material such as engineering plastic.

[0111] As illustrated in FIG. 3, the frame portion (338) is formed in the shape of a disc having a predetermined thickness and may be provided with an insertion groove (3381) that accommodates one end of the wrap portion (337). The insertion groove (3381) may be a spiral insertion groove formed by being recessed into one surface of the frame portion (338) in the same shape as the spiral cross-section of the wrap portion (337). In an alternative example not illustrated, the insertion groove (3381) of the frame portion (338) may be a spiral insertion hole formed to penetrate from one surface of the frame portion (338) to the other surface in the same shape as the spiral cross-section of the wrap portion (337). By inserting one end (337a) of the wrap portion (337) into the insertion groove (3381) or insertion hole of the frame portion (338), the frame portion (338) and the wrap portion (337) may be combined to form a rotating scroll (33).

[0112] Meanwhile, FIG. 6 is a perspective view illustrating a fixed scroll (32) of a scroll compressor (1) according to one embodiment of the present invention.

[0113] Except for the fact that the fixed scroll (32) includes a scroll side wall portion (322) that extends from the outer circumference of one side of the fixed plate (321) to wrap around the outer surface of the fixed wrap (323), the fixed scroll (32) can also be configured in the same way as the previously described rotary scroll (33) in that it includes two parts made of different materials, namely a wrap portion (327) made of metal material and a frame portion (328) made of resin material.

[0114] In the fixed scroll (32) of the present invention, a wrap portion (327) made of a metal material constitutes the fixed wrap (323). Similar to the rotating scroll (33) described above, the wrap portion (327) of the fixed scroll (32) can be formed by sintering powder of an iron-based material, or by precision forging, precision casting, or precision die casting of an iron-based material. Additionally, the wrap portion (327) may have an uneven space (not shown) formed to allow a part of the frame portion (328) to penetrate.

[0115] The frame portion (328) comprises a fixed plate (321) and a scroll side wall portion (322), excluding the fixed wrap (323). The frame portion (328) may be made of a resin material, and an insertion groove or insertion hole may be formed in the portion where one end of the wrap portion (327) is joined, into which one end of the wrap portion is inserted.

[0116] Next, a method for manufacturing scrolls (32, 33) for a scroll compressor, each comprising a wrap portion (327, 337) and a frame portion (328, 338) made of different types of materials as described above, will be explained. In the following description, the method for manufacturing a rotating scroll (33) will be explained as an example. However, a person skilled in the art will know that a fixed scroll (32) can also be manufactured in the same way. Accordingly, the method for manufacturing a fixed scroll (32) is not separately described in this specification.

[0117] FIG. 7 is a flowchart illustrating a method for manufacturing a rotating scroll manufactured by a scroll manufacturing method according to one embodiment of the present invention.

[0118] First, in step (S110), the wrap portion (337) is formed.

[0119] The wrap portion (337) may be made of a metal material, for example, an iron-based material. Additionally, the wrap portion (337) may be formed through precision processing such as sintering, precision forging, precision casting, or precision die casting.

[0120] Unlike forming through conventional casting, if the lap portion (337) is formed using precision machining such as sintering, precision forging, precision casting, or precision die casting, the lap portion (337) of the swivel scroll (33) manufactured by the scroll manufacturing method according to one embodiment of the present invention may be formed to have the final dimensions of the swivel lap (332) or to have increased dimensions that can be machined to the final dimensions through a single machining process. In this specification, a single machining process means, for example, machining to the target dimensions using only a single tool without changing the tool used for cutting, for example, a milling tool.

[0121] In this embodiment, the increased dimension may be, for example, 5 μm to approximately 200 μm, preferably approximately 150 μm.

[0122] In one example, following step (S110), optionally, a step of removing the enlarged dimensions of the wrap portion (337) may be performed. Since the enlarged dimensions of the wrap portion (337) formed through precision machining are dimensions that can be processed into final dimensions through a single machining process, this step can be completed in a single process.

[0123] If the dimensions of the molded wrap portion (337) are within the error range of the final dimensions, for example, less than 5 μm, the step of removing the increased dimensions may be omitted.

[0124] In another example, the increased dimensions of the wrap portion (337) may be removed along with the increased dimensions of the frame portion (338) in the step (S130) described later.

[0125] In a preferred embodiment, the wrap portion (337) can be formed by sintering a powder of an iron-based material.

[0126] When the wrap portion (337) is formed by sintering, the final dimensions of the swivel wrap (332) can be obtained by not performing a processing process on the wrap portion (337) as described above, or by performing only a single processing process.

[0127] In addition, the molded wrap portion (337) includes an uneven space (3371) on its interior and surface, which consists of pores that are naturally formed as a characteristic of sintering (Fig. 5a). In the step (S120) described later, the resin material of the frame portion (338) penetrates into the uneven space (3371) of the wrap portion (337), thereby allowing the wrap portion (337) to be more firmly bonded to the frame portion (338) (Fig. 9).

[0128] In an alternative embodiment, the wrap portion (337) may be formed by precision forging, precision casting, or precision die casting. Even with such precision machining, it is possible to obtain the final dimensions of the swivel wrap (332) by not performing a machining process on the wrap portion (337) as described above, or by performing only a single machining process.

[0129] However, the lap portion (337) formed by precision forging, precision casting, or precision die casting does not include an uneven space (3371) formed by pores such as the lap portion (337) formed by the aforementioned sintering.

[0130] In this case, step (S112) may be performed optionally. In step (S112), the surface of the wrap portion (337) is processed to artificially form an uneven space (3372) on the surface of the wrap portion (337) as shown in FIG. 5b. The processing to form the uneven space (3372) may be performed on the surface of the wrap portion (337) that is received in the insertion groove (3881) of the frame portion (338). The uneven space (3372) may be formed, for example, by sandblasting, etching, cutting, or laser processing.

[0131] The uneven space (3372) of the wrap portion (337) formed by step (S112) can have the resin material of the frame portion (338) penetrate into it, just like the uneven space (3371) made of pores of the sintered wrap portion (337) shown in FIG. 5a, and accordingly, the wrap portion (337) can be more firmly bonded to the frame portion (338).

[0132] Next, in step (S120), a resin material is inserted into one end of the wrap portion (337) to form the frame portion (338).

[0133] Insert injection can be performed by inserting the wrap portion (337) formed in step (S110) into a mold (90) as shown in FIG. 8 as an insert, and injecting a molten resin material, for example, an engineering plastic material, into the mold (90).

[0134] Through the insert injection of step (S120), a frame part (338) made of resin material is molded, and at the same time, the molded frame part (338) can be combined with the metal wrap part (337) molded in step (S110).

[0135] In step (S120), the molten resin injected into the mold (90) penetrates into the uneven spaces (3371, 3372) of the wrap portion (337), and accordingly, the bonding strength between the wrap portion (337) and the frame portion (338), which are molded from different materials, can be improved.

[0136] At this stage, the frame portion (338) may have the final dimensions of the pivot plate (331) or may have increased dimensions such that the final dimensions can be obtained in a single processing step. The increased dimensions of the frame portion (338) may also be larger than the final dimensions, for example, by 5 μm to approximately 200 μm, preferably approximately 150 μm.

[0137] When the wrap portion (337) is sintered and molded, an uneven space (3371) that naturally forms a pore shape through sintering can be formed. Therefore, sintering and molding the wrap portion (337) in step (S110) may be advantageous compared to molding the wrap portion (337) by other methods, as there is no need to perform an additional step (S112) to form the uneven space (3372).

[0138] Next, in step (S130), the rotating scroll (33) obtained in step (S120) is processed to achieve the final dimensions of the rotating scroll (33).

[0139] If an additional step of removing the increased dimensions of the wrap portion (337) is performed after step (S110), then in step (S130), only the increased dimensions of the frame portion (338) may be removed.

[0140] If the step of removing the increased dimensions of the wrap portion (337) was not performed, then in this step (S130), processing to simultaneously remove the increased dimensions of the wrap portion (337) and the increased dimensions of the frame portion (338) can be performed.

[0141] As previously explained, the increased dimensions of the wrap portion (337) and the increased dimensions of the frame portion (338) are within a range that can be removed in a single machining process. Therefore, the final dimensions of the swivel scroll (33) can be achieved through a minimal machining process.

[0142] If the dimensions of the wrap portion (337) and frame portion (338) of the rotating scroll obtained in step (S120) are within the tolerance compared to the final dimensions, for example, less than 5 μm, step (S130) may be omitted.

[0143] Accordingly, without the need to perform complex and difficult processing in multiple stages as in the past, a rotating scroll (33) with final dimensions can be obtained through a minimal processing process after insert injection.

[0144] According to the scroll for a scroll compressor and the method for manufacturing the same according to one embodiment of the present invention as described above, dimensional accuracy can be increased by sintering and molding the wrap portion and insert-injecting the frame portion, and the final dimensions of the swivel scroll or fixed scroll can be obtained through a minimal machining process after the insert-injection process. Accordingly, the dimensional accuracy required for the swivel scroll or fixed scroll can be achieved with minimal machining.

[0145] In addition, by minimizing the processing steps in this way, the manufacturing cost of the rotating scroll or fixed scroll and the scroll compressor including them can also be reduced.

[0146] In addition, according to a scroll for a scroll compressor and a method for manufacturing the same according to one embodiment of the present invention, instead of manufacturing the entire rotating scroll or fixed scroll from an iron-based material as in the prior art, the weight of the rotating scroll or fixed scroll and the scroll compressor including it can be reduced by molding the frame portion, which is the remaining part excluding the wrap portion forming the compression chamber, from a lightweight material such as engineering plastic.

Claims

1. A rotating scroll that performs a rotating motion; and It includes a fixed scroll that is coupled to the aforementioned rotating scroll and forms a compression chamber together with the aforementioned rotating scroll, and At least one of the above-mentioned rotating scroll and the above-mentioned fixed scroll is, A wrap portion constituting the pivot wrap of the pivot scroll or the fixed wrap of the fixed scroll; and It includes a frame portion coupled to one end of the above-mentioned wrap portion to form the pivot plate of the above-mentioned pivot scroll or the fixed plate of the above-mentioned fixed scroll, and A scroll compressor in which the frame portion is made of a material with lower strength than the wrap portion.

2. In Paragraph 1, A scroll compressor in which an uneven space is formed in the portion of the above-mentioned wrap part that contacts the above-mentioned frame part so that a part of the frame part penetrates.

3. In Paragraph 2, The above-mentioned uneven space is a scroll compressor in which the pattern is formed irregularly.

4. In Paragraph 2, The above-mentioned uneven space is a scroll compressor in which the pattern is regularly formed.

5. In Paragraph 1, The above frame part is a scroll compressor made of resin material.

6. In Paragraph 1, A scroll compressor having an insertion groove in which one end of the wrap portion is inserted on a surface that is coupled to one end of the wrap portion, the above-mentioned frame portion.

7. A step of forming a lap portion constituting the turning lap of a turning scroll or the fixed lap of a fixed scroll; and The method includes the step of forming a frame portion constituting the pivot plate of the pivot scroll or the fixed plate of the fixed scroll. The above-mentioned wrap portion has dimensions identical to the final dimensions of the above-mentioned swivel wrap or the above-mentioned fixed wrap, or has increased dimensions that can be processed to the final dimensions through a single machining process, and A method for manufacturing a scroll for a scroll compressor in which the above-mentioned frame portion is made of a material with lower strength than the above-mentioned wrap portion.

8. In Paragraph 7, After the step of forming the above-mentioned wrap portion, A method for manufacturing a scroll for a scroll compressor, further comprising the step of forming an uneven space such that a part of the frame penetrates into the portion where the above-mentioned wrap portion contacts the above-mentioned frame portion.

9. In Paragraph 8, A method for manufacturing a scroll for a scroll compressor in which the above-mentioned uneven space is formed by sandblasting, etching, cutting, or laser processing.

10. In Paragraph 7, A method for manufacturing a scroll for a scroll compressor in which the above-mentioned frame portion is molded by insert injection at one end of the above-mentioned wrap portion.

11. In Paragraph 7, The above-mentioned wrap portion is a method for manufacturing a scroll for a scroll compressor, formed by sintering iron-based material powder.

12. In Paragraph 7, After the step of forming the above-mentioned wrap portion and before the step of forming the above-mentioned frame portion, A method for manufacturing a scroll for a scroll compressor, further comprising the step of removing the increased dimensions of the wrap portion to obtain the final dimensions of the wrap portion.

13. In Paragraph 7, The above frame portion has increased dimensions that can be processed into the final dimensions of the swivel plate or fixed plate through a single machining process, and A method for manufacturing a scroll for a scroll compressor is, After the step of forming the above-mentioned frame part, A method for manufacturing a scroll for a scroll compressor, further comprising the step of obtaining the final dimensions of the rotary scroll or the fixed scroll by removing the increased dimensions of the above-mentioned wrap portion and the increased dimensions of the above-mentioned frame.

14. A step of forming a lap portion constituting the swivel lap of a swivel scroll or the fixed lap of a fixed scroll by sintering iron-based powder; A step of forming a frame portion constituting a pivot plate of the pivot scroll or a fixed plate of the fixed scroll by insert injection molding a resin material into the above-mentioned wrap portion; and The method includes the step of processing the above-mentioned wrap portion and the above-mentioned frame portion to obtain the final dimensions of the above-mentioned rotary scroll or the above-mentioned fixed scroll, and A method for manufacturing a scroll for a scroll compressor having increased dimensions, wherein, prior to the step of obtaining the above final dimensions, either one or both of the wrap portion and the frame portion can obtain the above final dimensions through a single machining process.

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