Scroll compressor

Abstract

The present invention discloses a scroll compressor (100) comprising: a sealed container (1); a crankshaft (4); a guide frame (50), the guide frame including a guide frame main portion (52) to which a fixed scroll member (30) is attached, and a guide frame extension portion (54) formed at the bottom of the guide frame main portion (52) and configured to support the crankshaft (4); and a compliant frame (60) supporting a movable scroll member (40), radially supporting the crankshaft (4) that drives the movable scroll member (40), and including a compliant frame main portion (62) supported by the guide frame main portion (52) and a compliant frame extension portion (64) supported by the guide frame extension portion (54). The crankshaft (4) is rotatably supported by bearings, the bearings including a lower bearing (70) attached to the guide frame extension portion (54) for rotatably supporting the crankshaft (4).

Description

Technical Field

[0001] This invention relates to scroll compressors. Background Technology

[0002] A known scroll compressor includes a crankshaft configured to transmit the rotational force of an electric motor to the scroll compressor mechanism and is disposed within a guide frame and a compliant frame radially supported by the guide frame, as disclosed in Japanese Unexamined Patent Application Publication No. H11-107938A1, hereinafter referred to as PTL1.

[0003] In the PTL1, the crankshaft is rotatably supported by an upper bearing and a lower bearing fixed to a conformal frame. The upper bearing is fixed to the upper portion of an extension of the conformal frame, and the lower bearing is fixed to the lower portion of the extension of the conformal frame. Furthermore, the eccentric shaft portion of the crankshaft located above the electric motor is rotatably supported in the radial direction by a cylindrical rotating bearing of a moving scroll member.

[0004] During normal operating conditions, the high-pressure refrigerant compressed in the compression chamber formed by the moving scroll and the stationary scroll causes the moving scroll to rise. The compression chamber of the scroll compressor mechanism is formed as a sealed compression chamber.

[0005] However, since the eccentric shaft section is set as the upper part of the crankshaft, centrifugal force acts on the eccentric shaft section during high-speed operating conditions, which may cause the crankshaft to bend from the position where the lower part of the crankshaft is supported by the subframe.

[0006] Therefore, the movement of the moving scroll and the compliant frame may become unstable, which could lead to refrigerant leakage from the compression chamber and reduce the volumetric efficiency of the compressor.

[0007] Therefore, there is a need to develop scroll compressors that can prevent volumetric efficiency loss even during high-speed operating conditions. Citation List Patent documents

[0008] PTL1: Japanese Unexamined Patent Application Publication No. H11-107938A1 Summary of the Invention

[0009] The purpose of this invention is to provide a scroll compressor that can prevent volumetric efficiency loss even during high-speed operation.

[0010] To achieve the above objectives, embodiments of the present invention provide a scroll compressor comprising: a sealed container; an electric motor housed within the sealed container; a crankshaft including a main crankshaft portion extending along its axis and an eccentric crankshaft portion formed as a top portion of the crankshaft and eccentric relative to the main crankshaft portion; and a scroll compression mechanism housed within the sealed container and configured to be driven by the crankshaft of the electric motor. The scroll compression mechanism includes a stationary scroll and a moving scroll. In the stationary scroll, a helical scroll of the stationary scroll stands upright on a base plate of the stationary scroll. In the moving scroll, a helical scroll of the moving scroll stands upright on a base plate of the moving scroll. The moving scroll is configured to engage with the stationary scroll to form a compression chamber between the stationary scroll and the moving scroll. The moving scroll includes a rotating bearing into which the eccentric crankshaft portion is inserted. The system comprises: a drive scroll member that rotates around a fixed scroll member, the drive scroll member being configured to rotate relative to a fixed scroll member; a guide frame to which the fixed scroll member is attached and the periphery of the guide frame is attached to a sealed container; the guide frame including a main portion to which the fixed scroll member is attached and a guide frame extension formed at the bottom of the main portion of the guide frame and configured to support a crankshaft; a compliant frame supporting the drive scroll member and radially supporting the crankshaft that drives the drive scroll member; the compliant frame including a main portion supported by the main portion of the guide frame and a compliant frame extension supported by the guide frame extension; a subframe radially supporting a lower portion of the crankshaft and the periphery of the subframe being attached to a sealed container; and wherein the crankshaft is rotatably supported by bearings, the bearings including a lower bearing attached to the guide frame extension for rotatably supporting the crankshaft.

[0011] According to an embodiment of the present invention, the lower bearing is attached to the guide frame extension for rotatably supporting the crankshaft.

[0012] In other words, in addition to being supported by the subframe, the crankshaft is also directly rotatably supported by the lower bearing attached to the guide frame extension without the need for a compliant frame.

[0013] Therefore, the bending angle, which is the angle at which the crankshaft bends from the position where the lower part of the crankshaft is supported by the subframe, can be reduced.

[0014] Even during high-speed operating conditions, the moving scroll is lifted upward by the high-pressure refrigerant compressed in the compression chamber formed by the moving scroll and the stationary scroll.

[0015] Therefore, even during high-speed operating conditions, scroll compressors can prevent loss of volumetric efficiency. Attached Figure Description

[0016] The principles and advantages of the invention will become apparent in the following description taking into consideration the accompanying drawings, in which:

[0017] Figure 1 This is a longitudinal cross-sectional view illustrating a schematic configuration of a scroll compressor 100 according to an embodiment of the present invention.

[0018] Figure 2 yes Figure 1 Explanatory diagram of the scroll compressor mechanism 20 and crankshaft 4;

[0019] Figure 3A This is a cross-sectional view of the guidance frame 50; and

[0020] Figure 3B This is a plan view of the guide frame 50. Detailed Implementation

[0021] In the following, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic longitudinal cross-sectional view of a scroll compressor 100 according to an embodiment. The scroll compressor 100 is a fluid machine configured to compress and discharge a fluid (i.e., a gaseous refrigerant), and can be a component of a refrigeration cycle device. The scroll compressor 100 according to this embodiment is a compressor with its housing mounted vertically.

[0023] like Figure 1 The scroll compressor 100 shown includes: a sealed container 1; a suction pipe 5, which is installed through to the top surface of the sealed container 1 and is formed as a hollow cylindrical pipe; a discharge pipe 6, which discharges gaseous refrigerant to the outside; a scroll compression mechanism 20, which is configured to compress low-pressure gaseous refrigerant in a compression chamber 22; an electric motor 2, which is configured to drive the scroll compression mechanism 20 housed in the sealed container 1; and a crankshaft 4, which includes a main crankshaft portion 4a and an eccentric crankshaft portion 4b eccentric to the main crankshaft portion 4a.

[0024] The outer periphery of the scroll compressor 20 is fastened to the guide frame 50 by bolts (not shown). The outer periphery of the guide frame 50 is attached to the sealing container 1 by a shrink fit or other method. A sub-frame 7 is provided below the electric motor 2. The sub-frame 7 is fixed to the inner circumferential surface of the sealing container 1. The sub-frame 7 radially supports the lower portion of the crankshaft 4 and its periphery is attached to the sealing container 1.

[0025] A suction pipe 5, configured to draw low-pressure gaseous refrigerant from the outside into the scroll compressor 20, is connected to the side surface of the sealed container 1. A discharge pipe 6, configured to discharge high-pressure gaseous refrigerant to the outside of the scroll compressor 100, is connected to the side surface of the sealed container 1.

[0026] A scroll compressor 20 is housed in a sealed container 1 and is configured to compress gaseous refrigerant drawn in from the intake pipe 5 by rotation of a crankshaft 4 driven by an electric motor 2. Figure 1 The scroll compression mechanism 20 shown includes a fixed scroll 30 and a moving scroll 40.

[0027] like Figure 1 and Figure 2 As shown, the fixed vortex member 30 includes: a fixed vortex member base plate 31; and a helical fixed vortex member vortex 32 having an involute curve shape to form a helical body and stand upright on one surface of the fixed vortex member base plate 31. A discharge port 30a configured to discharge compressed gaseous refrigerant is formed in the central portion of the fixed vortex member 30.

[0028] In addition, the fixed scroll member 30 includes an intake communication passage (not shown) configured such that refrigerant flowing through the intake pipe 5 is guided to the compression chamber 22.

[0029] like Figure 1 and Figure 2 As shown, the moving scroll member 40 is configured to revolve around the stationary scroll member 30 without rotating, via an Oldham (not shown) cross-slider mechanism. The moving scroll member 40 includes: a moving scroll member base plate 41; and a helical moving scroll member scroll 42 having an involute curve shape to form a helical body and stand upright on one surface of the moving scroll member base plate 41. A revolute bearing 43, formed in a bottom cylindrical shape, is formed in the approximately central portion of the lower surface of the moving scroll member base plate 41. An eccentric portion 4b of the crankshaft, mounted on the upper end of the crankshaft main portion 4a (described later), is inserted into the revolute bearing 43 to cause the moving scroll member 40 to revolve.

[0030] The moving scroll 42 is configured to engage with the fixed scroll 32 to form a scroll compression chamber 22 between the fixed scroll 32 and the moving scroll 42. The moving scroll 40 is configured to rotate relative to the fixed scroll 30.

[0031] like Figure 1As shown, the electric motor 2 includes: an electric motor stator 2a, which is fixed to the inner circumferential surface of the sealed container 1 by a shrink fitting or other method; and an electric motor rotor 2b, which is rotatably housed on the inner circumferential side of the electric motor stator 2a. A crankshaft main portion 4a is inserted into and fixed to the electric motor rotor 2b. The electric motor rotor 2b is configured to rotate when power is supplied to the electric motor stator 2a and to transmit driving force to the moving scroll member 40 via the crankshaft 4.

[0032] like Figure 1 and Figure 2 The scroll compressor 100 shown includes: a compliant frame 60 that axially supports a movable scroll 40 and radially supports a crankshaft 4 that drives the movable scroll 40; and a guide frame 50 that radially supports the compliant frame 60. As mentioned above, a stationary scroll 30 is attached to the guide frame 50 and the periphery of the guide frame 50 is attached to the sealed container 1.

[0033] Furthermore, the guide frame 50 includes: a guide frame main portion 52, on which a fixed vortex member 30 is attached and the periphery of the guide frame main portion 52 is attached to the sealing container 1; and a guide frame extension portion 54, formed at the bottom of the guide frame main portion 52 and configured to support the crankshaft 4. The compliant frame 60 includes a compliant frame main portion 62 supported by the guide frame main portion 52 and a compliant frame extension portion 64 supported by the guide frame extension portion 54.

[0034] like Figure 3A and Figure 3B As shown, an annular jaw portion 56 is formed at the lower end of the guide frame extension 54, extending toward the crankshaft 4 and rotatably supporting the crankshaft 4. Furthermore, the jaw portion 56 has at least one through hole 58 extending from the upper surface 56a of the jaw portion 56 to the lower surface 56b of the jaw portion 56, allowing high-pressure gas refrigerant to flow into the gap between the lower end of the compliant frame extension 64 and the guide frame extension 54.

[0035] In this embodiment, the number of through holes 58 is eight, but the number of through holes 58 is not limited to eight, as long as the pressure of the compressed gaseous refrigerant acts evenly on the lower end of the compliant frame extension 64 of the compliant frame 60. When there are multiple through holes 58, it is preferable that the through holes 58 are formed symmetrically around the crankshaft 4, so that the pressure of the compressed gaseous refrigerant acts more evenly on the lower end of the compliant frame extension 64 of the compliant frame 60.

[0036] like Figure 1and Figure 2 As shown, the base plate 41 of the moving scroll member is fixed to the upper surface of the main part 62 of the compliant frame. The moving scroll member 40 and the compliant frame 60 are provided with a pressure equalization channel 66 through which gaseous refrigerant can flow, thereby extending from the compression chamber 22 in the scroll compressor mechanism 20 to the gap between the compliant frame extension 64 and the guide frame extension 54.

[0037] In this embodiment, the crankshaft 4 is rotatably supported by bearings. The bearings include: an annular lower bearing 70, attached to a guide frame extension 54, for rotatably supporting the crankshaft 4; and an annular upper bearing 72, attached to a compliant frame extension 64, for rotatably supporting the crankshaft 4. Figure 3A and Figure 3B As shown, the lower bearing 70 is attached to the crankshaft side of the jaw portion 56 of the guide frame extension 54.

[0038] Next, the operation of the scroll compressor 100 of this embodiment will be described.

[0039] First, under normal operating conditions, the compressed gaseous refrigerant in the compression chamber 22 flows through the pressure equalization channel 66 into the gap between the compliant frame extension 64 and the guide frame extension 54, thereby applying the pressure of the compressed gaseous refrigerant to the compliant frame 60. Then, the compliant frame 60 is lifted upward, i.e., towards the fixed scroll member side.

[0040] Therefore, the moving scroll member 40, fixed to the compliant frame 60, also rises upward, i.e., toward the fixed scroll member side. The moving scroll member base plate 41 and the moving scroll member scroll 42 of the moving scroll member contact the fixed scroll member base plate 31 and the fixed scroll member scroll 32 of the fixed scroll member 30 and slide on the fixed scroll member base plate 31 and the fixed scroll member scroll 32 of the fixed scroll member 30, thus forming a compression chamber 22.

[0041] Furthermore, the compressed gaseous refrigerant compressed in the compression chamber 22 flows through the through-hole 58 into the gap between the lower end of the compliant frame extension 64 and the guide frame extension 54. Therefore, the compliant frame 60 also rises upward, i.e., toward the fixed scroll member side.

[0042] Therefore, the compressed gaseous refrigerant flowing through the pressure equalization channel 66 into the gap between the compliant frame extension 64 and the guide frame extension 54, and the compressed gaseous refrigerant flowing through the through hole 58 into the gap between the lower end of the compliant frame extension 64 and the guide frame extension 54, cause the moving scroll member 40 to rise together with the compliant frame 60, and the compression chamber 22 is formed by the moving scroll member 40 and the fixed scroll member 30.

[0043] Secondly, under high-speed operating conditions, since the eccentric portion 4b of the crankshaft is set as the upper part of the crankshaft 4, a larger centrifugal force acts on the eccentric portion 4b during high-speed operation. Therefore, a force that tends to bend the crankshaft 4 from the position where the lower part of the crankshaft 4 is supported by the subframe 7 acts on the crankshaft 4.

[0044] Since the crankshaft 4 is rotatably supported by bearings—including a lower bearing 70 attached to the guide frame extension 54 for rotatably supporting the crankshaft 4 and an upper bearing 72 attached to the compliant frame extension 64 for rotatably supporting the crankshaft 4—the crankshaft 4 is directly supported by the lower bearing 70 fixed to the extension of the guide frame 50 without the intervention of the compliant frame 60. Therefore, the bending angle, which is the angle at which the crankshaft 4 bends from its position where its lower portion is supported by the sub-frame 7, can be reduced. Furthermore, since the crankshaft 4 is rotatably supported by the upper bearing, the compliant frame 60 and the moving scroll member 40 are smoothly lifted upwards to form a predetermined compression chamber 22 by the fixed scroll member 30 and the moving scroll member 40.

[0045] In other words, even during high-speed operating conditions, the moving scroll 40 is raised to form a predetermined compression chamber 22 through the stationary scroll 30 and the moving scroll 40, and the moving scroll 40 and the compliant frame 60 remain stable and do not tilt during high-speed operating conditions. Therefore, gaps that could lead to leakage of compressed gaseous refrigerant can be prevented between the stationary scroll base plate 31 and the moving scroll 42, and / or between the moving scroll base plate 41 and the stationary scroll 32.

[0046] In the compressor industry, volumetric efficiency, defined as the ratio of the actual refrigerant flow rate to the discharge volume, is typically used as an indicator of the performance of a scroll compressor 100. According to the compressor, even during high-speed operating conditions, loss of volumetric efficiency can be prevented.

[0047] Furthermore, in this embodiment, an annular jaw portion 56 extending toward and rotatably supporting the crankshaft 4 is formed at the lower end of the guide frame extension portion 54, and the jaw portion 56 has eight through holes 58 penetrating from the upper surface 56a to the lower surface 56b. Even during high-speed operating conditions, the moving scroll member 40 is lifted upward by the high-pressure refrigerant compressed within the compression chamber 22 formed by the moving scroll member 40 and the stationary scroll member 30.

[0048] In particular, because the through-hole 58 is formed symmetrically around the axis of the crankshaft 4, the upward movement of the moving scroll 40 and the compliant frame 60, caused by the high-pressure refrigerant compressed within the compression chamber 22, becomes stable. As a result, the compressor can more reliably prevent loss of volumetric efficiency, even during high-speed operating conditions.

[0049] Although specific embodiments of the invention have been disclosed, described, and illustrated in the accompanying drawings, this is merely for the purpose of better understanding the principles of the invention and not intended to limit the scope and spirit of the invention. Various adjustments and modifications to the structure, such as design or materials, of the invention will be possible and apparent to those skilled in the art without departing from the scope of the invention as defined by the claims.

[0050] List of reference numerals in the attached diagram:

[0051] 100: Scroll compressor

[0052] 1: Sealed container

[0053] 2: Electric motor

[0054] 2a: Electric motor stator

[0055] 2b: Electric motor rotor

[0056] 4: Crankshaft

[0057] 4a: Main parts of the crankshaft

[0058] 4b: Crankshaft eccentric part

[0059] 5: Suction tube

[0060] 6: Drainage pipes

[0061] 7: Subframe

[0062] 20: Scroll compressor mechanism

[0063] 22: Compression Chamber

[0064] 30: Fixed vortex component

[0065] 30a: Emission port

[0066] 31: Base plate of fixed vortex component

[0067] 32: Fixed vortex component vortex

[0068] 40: Moving scroll component

[0069] 41: Base plate of moving scroll component

[0070] 42: Moving scroll component scroll

[0071] 43: Rotating bearing

[0072] 50: Guiding Framework

[0073] 52: Main Components of the Guidance Framework

[0074] 54: Guiding Frame Extension

[0075] 56: Jaw section

[0076] 56a: Upper surface

[0077] 56b: Lower surface

[0078] 58: Through hole

[0079] 60: Adaptability Framework

[0080] 62: Main Components of the Adaptability Framework

[0081] 64: Adaptability Framework Extension

[0082] 66: Pressure Equalization Channel

[0083] 70: Lower bearing

[0084] 72: Upper bearing

Claims

1. A scroll compressor (100), comprising: Sealed container (1); An electric motor (2) is housed in the sealed container (1); The crankshaft (4) includes a main crankshaft portion (4a) extending along the axis of the crankshaft (4) and an eccentric crankshaft portion (4b) formed as the top portion of the crankshaft (4) and eccentric relative to the main crankshaft portion (4a). A scroll compressor mechanism (20) is housed in the sealed container (1) and configured to be driven by the crankshaft (4) of the electric motor (2). The scroll compressor mechanism (20) includes a fixed scroll (30) and a moving scroll (40). In the fixed scroll (30), a helical scroll (32) stands on the base plate (31) of the fixed scroll. In the moving scroll (40), a helical scroll (42) stands on the base plate (31) of the moving scroll. On the base plate (41), the moving scroll (42) is configured to engage with the fixed scroll (32) to form a compression chamber (22) between the fixed scroll (32) and the moving scroll (42). The moving scroll (40) includes a rotating bearing (43), and the crankshaft eccentric portion (4b) is inserted into the rotating bearing (43) to rotate the moving scroll (40). The moving scroll (40) is configured to rotate relative to the fixed scroll (30). A guide frame (50), the fixed scroll member (30) is attached to the guide frame (50) and the periphery of the guide frame (50) is attached to the sealed container (1), the guide frame (50) includes: a guide frame main portion (52), the fixed scroll member (30) is attached to the guide frame main portion (52); and a guide frame extension portion (54), the guide frame extension portion (54) is formed at the bottom of the guide frame main portion (52) and configured to support the crankshaft (4); A compliant frame (60) supports the moving scroll (40) and radially supports the crankshaft (4) that drives the moving scroll (40). The compliant frame (60) includes a compliant frame main portion (62) supported by the guide frame main portion (52) and a compliant frame extension portion (64) supported by the guide frame extension portion (54). Subframe (7), which radially supports the lower portion of the crankshaft (4) and whose periphery is attached to the sealed container (1); and The crankshaft (4) is rotatably supported by a bearing, the bearing including a lower bearing (70) attached to the guide frame extension (54) for rotatably supporting the crankshaft (4).

2. The scroll compressor (100) according to claim 1, wherein, The bearing includes an upper bearing (72) attached to the compliant frame extension (64) for rotatably supporting the crankshaft (4).

3. The scroll compressor (100) according to claim 1, wherein, An annular jaw portion (56) is formed at the lower end of the guide frame extension (54) extending toward the crankshaft (4) and rotatably supporting the crankshaft (4), wherein the lower bearing (70) is attached to the crankshaft side of the jaw portion (56), and wherein the jaw portion (56) is formed with at least one through hole (58) penetrating from the upper surface (56a) of the jaw portion (56) to the lower surface (56b).

4. The scroll compressor (100) according to claim 3, wherein, The number of the through holes (58) is at least two, and the through holes (58) are formed symmetrically around the crankshaft (4).

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