JP2017053229A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor in which an electrolytic corrosion at a roller bearing can be prevented by low cost material.SOLUTION: This invention relates to a scroll compressor featuring that there are provided, within a hermetic container 100: a compression mechanism including a fixed scroll and a revolving scroll; an electric motor part for driving the compression mechanism; a vertical shaft type rotating shaft 101 for transmitting a rotating force of the electric motor part to the compression mechanism; a sub-bearing 105 arranged to enclose the rotating shaft to support the rotating shaft; a housing 133 for supporting the sub-bearing; an oil reservoir part for storing lubricant oil; and an oil supply passage for supplying lubricant oil kept in the oil reservoir part to the sub-bearing through the rotating shaft; and a lower frame 137 fixed in the hermetic container and the housing are fastened with bolts and fixed. When the lower frame and the housing are fastened with the bolts, an insulation sheet 190 is placed between the housing and the lower frame, and both an insulation ring 191 and a metallic flat washer 192 are arranged between the housing and a bolt 138 to perform an electrical insulation at the sub-bearing.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a scroll compressor that handles HFC refrigerant, natural refrigerant air, carbon dioxide, and other compressible gases, and in particular, to reduce bearing damage caused by bearing electric corrosion and improve bearing reliability. The present invention relates to a suitable scroll compressor.

  Positive displacement compressors are widely used in various fields as compressors for refrigeration and air conditioning equipment. Due to energy conservation regulations to prevent global warming, the efficiency of compressors is rapidly increasing. On the other hand, it is essential that the sliding portion is not damaged even when a very severe operation is performed. In recent years, inverter control of drive motors has become mainstream in compressors in order to increase efficiency. By increasing this control frequency (carrier frequency), it is possible to further increase the motor efficiency. However, as the carrier frequency increases, an event that causes an increase in high-frequency current flowing through the bearing portion may occur.

  As a countermeasure against such a problem, Patent Document 1 states that “a rolling element of a rolling bearing is a ceramic manufactured by a normal pressure sintering method mainly composed of silicon nitride, zirconia, alumina, and silicon carbide to prevent electrolytic corrosion. In addition, grease was attached to pores generated on the surface of the ceramic rolling element to form a grease reservoir, thereby improving the lubrication state and improving the durability. "

  Further, in Patent Document 2, “in order to prevent electric corrosion of a rolling bearing, an outer ring outer diameter surface that is a surface attached to a housing or a shaft or an inner ring inner diameter surface is provided with an insulating layer that is a ceramic sprayed layer. It has excellent linearity and a low coefficient of linear expansion, so it can prevent the fitting error of the fitting part due to bearing heat generation, and has been put to practical use for main motors, driving devices, and axles of railway vehicles. Yes.

  In Patent Document 3, “In order to improve year-round energy consumption efficiency (APF) and period performance coefficient (IPLV), the requirements of energy efficiency improvement at low load and rapid heating and rapid cooling at high load are satisfied. For this reason, in the positive displacement compressor, the driving current at the time of high load is larger than before, and the current flowing to the bearing portion is increased. In order to reduce the current flowing to the bearing, it is described that the neutral point of the three phases is connected.In addition, an insulating sheet (ceramics / insulating property is high in the engaging portion of the bearing housing and the lower frame). Insulation measures using resin) ”.

JP 2002-139048 A JP 2011-117607 A JP 2011-259646 A

  According to the technique described in Patent Document 1, the rolling element is composed of a rolling element incorporated between the outer ring and inner ring of the rolling bearing and the outer ring and the inner ring, and the rolling element is an atmospheric pressure mainly composed of silicon nitride, zirconia, alumina, and silicon carbide. A ceramic rolling element manufactured by a sintering method is used, and grease is attached to pores generated on the surface of the rolling element to improve the lubrication state and improve the durability.

  However, since the surface of the ceramic rolling element produced by the conventional pressure sintering method is densely formed, the pores are small and the surface is smooth, but the atmospheric pressure sintering method increases the pores as described above, When the surface becomes rough and the grease is depleted, there are a problem that reliability is lowered and a problem that it is expensive in terms of cost.

  According to the technique described in Patent Literature 2, an outer ring outer diameter surface that is a surface attached to a housing or a shaft or an inner ring inner diameter surface is provided with an insulating layer that is a ceramic sprayed layer in order to prevent rolling bearing electrolytic corrosion. As the ceramic material for the insulating layer, metal oxides such as alumina, gray alumina, titanium oxide, and chromium oxide are used. With this configuration, since the electrical insulation is excellent and the coefficient of linear expansion is small, it is possible to prevent the fitting error of the fitting portion due to the heat generation of the bearing.

  However, there is a problem that electrical breakdown may be caused after the bearing is inserted into the fitting portion with the housing or the shaft, and the ceramic sprayed coating is expensive in terms of cost.

  According to the technology described in Patent Document 3, in a positive displacement compressor designed to improve year-round energy consumption efficiency (APF) and period performance coefficient (IPLV), the driving current at a high load is higher than before. Cause an increase in current flowing to the bearing. For this reason, in order to reduce the electric current which flows into a bearing part, connecting the neutral point of 3 phases is described. Furthermore, an insulation measure using an insulating sheet (ceramics / resin having high insulating properties) at the engaging portion between the bearing housing and the lower frame is described. By connecting the neutral points of the above three phases, the current flowing to the bearing can be reduced. However, since the current cannot be made zero, it is necessary to take insulation measures.

  However, although measures against insulation are defined as ceramics or highly insulating resin (polyphenylene sulfide: PPS), there is a problem that detailed materials are not defined.

  From the above, the object of the present invention is not a member that supports rotational driving such as a housing around the rolling bearing constituting the auxiliary bearing or a fitting portion with the shaft, and an insulating sheet or the like between the bearing housing and the lower frame. Thus, it is possible to obtain a scroll compressor that can implement electric corrosion prevention of a rolling bearing with a low-cost material by defining a sheet material to be electrically insulated.

  In order to solve the problem, in the present invention, a compression mechanism including a fixed scroll and a turning scroll, an electric motor that drives the compression mechanism, and a rotational force of the electric motor in the compression mechanism A vertical axis rotating shaft that transmits, a sub-bearing that surrounds the rotating shaft and supports the rotating shaft, a housing that supports the sub-bearing, an oil reservoir that stores lubricating oil, and lubrication in the oil reservoir A scroll compressor having an oil supply path for supplying oil to a sub-bearing through a rotating shaft and fixed between a lower frame and a housing fixed in a sealed container by bolting, the lower frame and the housing In order to bolt the gap between the housing and the lower frame, an insulating sheet was provided, and an insulating ring and a metal flat washer were provided between the housing and the bolt to make the secondary bearing electrically insulated. Feature To.

  According to the present invention, it is possible to prevent an electric current from flowing to the rolling bearing and to provide an inexpensive insulating material.

The figure which shows the whole structure of the general scroll compressor which can apply this invention. The figure which shows the structure by the conventional method which expanded and showed the auxiliary bearing attaching part A of FIG. The figure which shows the structure of the auxiliary bearing attaching part A which concerns on Example 1. FIG. The figure which expanded and displayed the bolt fastening part B of FIG. The figure which showed the tensile strength test equipment of the insulation sheet. The figure which showed the evaluation result of the tensile strength of an insulating sheet. The figure which showed the displacement amount measurement result of the insulating material. The graph which showed the relationship between the displacement measurement result of an insulating material, and tensile strength. The figure which shows the structure of the auxiliary bearing attaching part A which concerns on Example 2. FIG. The figure which shows the structure of the bolt fastening part B which concerns on Example 3. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The general structure of a general scroll compressor to which the present invention is applicable will be described in detail with reference to FIG.

  The scroll compressor 1 is configured by accommodating a compression mechanism unit 2 and a drive unit 3 in a sealed container 100 as main components.

  The compression mechanism unit 2 includes a fixed scroll 110, a turning scroll 120, and a frame 160. Of these, the fixed scroll 110 has an end plate 110b and a spiral wrap 110a standing vertically to the end plate 110b, a discharge port 110e at the center of the spiral wrap 110a, and a plurality of bolts on the frame 160. Is fixed through.

  The orbiting scroll 120 has an end plate 120b and a spiral wrap 120a erected perpendicularly to the end plate 120b, and includes a boss portion 120e and a boss portion end surface 120f on the back side of the end plate 120b.

  The compression chamber 130 configured by meshing the fixed scroll 110 and the orbiting scroll 120 performs a compression operation in which the volume thereof decreases as the orbiting scroll 120 orbits. In this compression operation, the working fluid is sucked into the compression chamber 130 from the suction port 140 along with the turning motion of the orbiting scroll 120, and the sucked working fluid passes through the compression stroke from the discharge port 110 e of the fixed scroll 110 to the sealed container 100. It is discharged into the discharge space 136 in the inside, and further discharged from the sealed container 100 via the discharge port 150. As a result, the space in the sealed container 100 is maintained at the discharge pressure.

  The drive unit 3 that orbits the orbiting scroll 120 includes an electric motor unit including the stator 108 and the rotor 107, the rotating shaft 101, an Oldham coupling 134 that is a main part of the rotation prevention mechanism of the orbiting scroll 120, a frame 160, It comprises a bearing 104, a secondary bearing 105, and a swivel bearing 103.

  The rotating shaft 101 is configured by integrally including a main shaft portion 101b and an eccentric pin portion 101a. The main bearing 104 and the sub-bearing 105 are configured to engage the rotating shaft 101 rotatably. The orbiting bearing 103 is provided in the boss portion 120e of the orbiting scroll so as to engage the eccentric pin portion 101a of the rotating shaft 101 so as to be movable in the direction of the rotating shaft and to be rotatable. A main bearing 104 and a sub-bearing 105 that rotatably engage the rotating shaft are arranged on the compression mechanism portion 2 side and the oil reservoir portion 131 side of the electric motor composed of the stator 108 and the rotor 107, respectively.

  Although it is desirable to use a rolling bearing for the main bearing 104 in the vicinity of the compression mechanism portion 2 side, a sliding bearing may be used. Further, a rolling bearing as shown in the drawing is inserted into the sub bearing 105 near the oil reservoir 131 and the housing 133 is fixed to the lower frame 137 tack-welded to the sealed container 100 via a plurality of bolts 138.

  The Oldham coupling 134 is disposed in a back pressure chamber 180 constituted by the orbiting scroll 120 and the frame 160 and is a rotation preventing member for the fixed scroll 110 and the orbiting scroll 120. One set of two orthogonal key portions formed on the Oldham coupling 134 slides on the key groove 141 formed on the frame 160, and the other set slides on the key groove formed on the back side of the orbiting scroll 120.

  A seal structure for pressure-separating the back pressure chamber 180 will be described with reference to FIG. The space configured on the back side of the orbiting scroll 120 is a space surrounded by the orbiting scroll 120, the frame 160, and the fixed scroll 110. Separating means for the high pressure chamber 181 and the back pressure chamber 180 are disposed in the boss end surface 120f on the back of the orbiting scroll, the ring-shaped groove 161 formed on the end surface portion of the frame facing this, and the ring-shaped groove 161. And a sealing member 172.

  Here, the boss portion end surface 120 f is a seal surface in contact with the seal member 172. The seal member 172 is a seal means that pressure-separates the back pressure chamber 180 and the high pressure chamber 181. The high-pressure chamber 181 seals the lubricating oil discharged from the slewing bearing 103, the main bearing 104, and the thrust bearing 204 with a seal member 172. The high-pressure chamber 181 has a pressure increasing action due to the pump action and a pressure reducing action when passing through the bearing part and the gap part. The pressure space is about the discharge pressure of what is received. In order to lubricate the sliding portion such as the Oldham coupling 134 disposed in the back pressure chamber 180, a small hole 170 for intermittently or continuously communicating the high pressure chamber 181 and the back pressure chamber 180 is provided in the end surface 120f of the boss portion. It is.

  Oil supply to the slewing bearing 103, the main bearing 104, and the sub bearing 105 is performed by an oil supply path 102 and an oil supply pump 106 provided in the rotary shaft 101. That is, the lubricating oil collected in the lower space of the sealed container 100 is sucked by the oil supply pump 106 and supplied to the slewing bearing 103 via the oil supply path 102, and the oil supply of the sub-bearing portion distributed from the oil supply path 102 A path for supplying lubricating oil to the auxiliary bearing 105 through the path 102a is provided. As the oil pump, a centrifugal pump action that is realized by an eccentric rotation operation that is configured in the rotation shaft 101 may be used, although not shown. The lubricating oil supplied to the slewing bearing 103 is finally collected in the oil reservoir 131 at the bottom of the sealed container 100 via the discharge passage 184 and recirculated.

  The general structure of a general scroll compressor to which the present invention is applicable is as described above. According to the present invention, in the overall configuration, a high carrier frequency for control flows to the bearing portion due to adopting inverter control of the drive motor for high efficiency, and the bearing portion is damaged. doing. A current including a high carrier frequency component circulates in a path from the stator 108 to the sealed container 100, the lower frame 137, the bolt 138, the housing 133, the auxiliary bearing 105, the rotating shaft 101, and the rotor 107, and damages the auxiliary bearing 105. .

  FIG. 2 is a diagram illustrating a conventional solution, and is a diagram illustrating a structure according to a conventional technique in which the auxiliary bearing mounting portion A of FIG. 1 is enlarged.

  In FIG. 2, when a rolling bearing is used as the auxiliary bearing 105, the auxiliary bearing 105 includes an inner ring 105a on the rotating shaft 101 side, an outer ring 105c on the housing 133 side, and a rolling element 105b between the inner ring 105a and the outer ring 105c. The The outer ring 105 c of the auxiliary bearing 105 is inserted into the inner peripheral surface of the housing 133. The housing 133 is connected to the lower frame 137 by bolts 138 and is fixed to the hermetic container 100 via the lower frame 137. In addition, bearing steel is used for the inner ring 105a and the outer ring 105c of the auxiliary bearing 105, and the rolling elements 105b therebetween are made of a ceramic material.

  According to the structure of FIG. 2 in the conventional method, the inner ring 105a and the outer ring 105c of the auxiliary bearing 105 are made of bearing steel, and the rolling element 105b between them is made of a ceramic material, thereby electrically insulating the inner ring 105a and the outer ring 105c. As a result, it is possible to prevent damage caused by a current including a high carrier frequency component flowing through the auxiliary bearing 105. In this case, since insulation between the housing 133 and the lower frame 137 is not necessary, it is only necessary to fasten with the metal bolts 138, but the auxiliary bearing 105 becomes an expensive bearing in terms of cost. I can't avoid it.

  FIG. 2 is a diagram illustrating the structure of the auxiliary bearing mounting portion A according to the first embodiment. In the present invention, as shown in FIG. 3 according to the first embodiment, the housing 133 is attached to the lower frame 137 with bolts 138 by bolting. At that time, an insulating sheet 190 is provided between the lower frame 137 and the bolt 138, an insulating ring 191 and a metal washer 192 are provided between the housing 133 and the bolt 138, and the lower frame 137 and the housing 133 are electrically connected. Insulate. With such a configuration, it is possible to prevent a current from flowing to the auxiliary bearing 105.

  FIG. 4 is an enlarged view of the bolt fastening portion B of FIG. In the embodiment of FIG. 4, in short, when connecting the upper and lower metal parts (housing 133, lower frame 137) with metal (bolt 138), an insulating material (insulating material) is used to prevent electrical conduction due to contact of the metal part through. A sheet 190 and an insulating ring 191) are installed. The insulating ring 191 is formed by forming a recess in a housing 133 that is a metal portion and fitting the ring there.

  In addition, in the present invention, the tightening pressure is set to 170 MPa or more after employing such a bolt tightening structure. In Example 1, the measurement results of the bonding strength when the housing 133 and the lower frame 137 are fastened with the bolts 138 are shown in FIGS.

  First, FIG. 5 is a diagram showing a tensile strength test facility for an insulating sheet, and a fastening force evaluation jig 210 corresponding to the lower frame 137 and a housing 133 are fastened with a plurality of bolts 138 via an insulating sheet 190. In this state, the amount of displacement of the housing 133 when the load is applied is measured.

  FIG. 6 is a diagram showing the evaluation results of the tensile strength of the insulating sheet. Here, the insulating sheet 190 is made of two types of resin materials (PPS + 30% glass fiber) obtained by blending glass fiber with tetrafluoroethylene resin (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and PPS. , PPS + 40% glass fiber). The insulating ring 191 was made of PPS + 40% glass fiber resin, and the flat washer 192 was made of metal and had an outer diameter of Φ15 mm and an inner diameter of Φ5 mm. The size of the bolt 138 was M5, and the six circumferential locations of the housing 133 were fixed with bolts.

  In the evaluation results of FIG. 6, the tensile strength (MPa) and the deflection temperature under load (° C.) were measured for each material. For tetrafluoroethylene resin (PTFE), the tensile strength (MPa) is 15 MPa and the deflection temperature under load (° C) is not measured. For polyphenylene sulfide (PPS), the tensile strength (MPa) is 90 MPa and the deflection temperature under load (° C) is Polyetheretherketone (PEEK) has a tensile strength (MPa) of 97 MPa, a deflection temperature under load (° C) of 155 ° C, and a PPS + 30% glass fiber has a tensile strength (MPa) of 170 MPa and a deflection temperature under load (° C) was 265 ° C., PPS + 40% glass fiber had a tensile strength (MPa) of 200 MPa and a deflection temperature under load (° C.) of 270 ° C.

  FIG. 7 is a diagram showing the measurement results of the displacement amount of the insulating material, and shows the measurement results of the displacement amount when the load load is set to 6000 N, which is five times or more the bearing load when the scroll compressor is actually operated. In FIG. 7, the conventional case is a case where metals are fastened without interposing an insulating sheet 190 between the lower frame 137 and the housing 133 (see FIG. 2). The amount of displacement in each case is indicated by the ratio.

  According to the evaluation result of FIG. 7, in the case of PPS + 30% glass fiber or PPS + 40% glass fiber, the amount of displacement is the same as that in the conventional case, whereas polyether ether ketone (PEEK) and polyphenylene sulfide (PPS) are 140. The amount of displacement is approximately%, and the amount of displacement is approximately 250% for tetrafluoroethylene resin (PTFE).

  As a result of evaluating the amount of displacement of the insulating sheet material, if the material containing glass fiber of PPS + 30% or higher with high tensile strength shown in FIG. However, it has been found that the electrical insulation of the rolling bearing can be secured. Here, an example is shown for polyphenylene sulfide (PPS), but similar characteristics can be obtained even with a material containing 30% or more glass fiber in polyether ether ketone (PEEK).

  FIG. 8 is a graph showing the relationship between the displacement measurement result of the insulating material and the tensile strength, and shows the relationship between the displacement amount ratio of FIG. 7 and the tensile strength of the insulating sheet material. As the tensile strength is increased, the displacement amount can be maintained at 100% (displacement equivalent to the conventional one). This result means that if the material contains PPS + 30% or more glass fiber, the tensile strength will be 170 MPa or more, and if it is a resin material having the same tensile strength, similar characteristics can be obtained. ing.

Now, further features of the present invention will be described with reference to a detailed view of the first embodiment shown in FIG. Here, by setting the ratio of the outer diameter size D and the inner diameter size d of the metal plain washer 192 to D / d ≧ 2, the axial force with which the bolt 138 is fastened to the lower frame 137 is applied to the plain washer 192 and the insulating ring 191. The surface pressure when acting on the surface can be reduced. For example, when the bolt of M5 is fastened with a torque T = 7 Nm, the axial force F is a value obtained by dividing the torque T by the torque coefficient k and the bolt diameter, and is a relational expression such as Expression (1).
F = T / (k · d) (1)
In this case, when the torque coefficient k is 0.15, the axial force F is 9333N, and when the outer diameter of the plain washer is 10 mm and the inner diameter is 5 mm, which is equal to the bolt diameter d, the surface pressure is 158 MPa. The surface pressure acts on the insulating ring 191 interposed between the flat washer 192 and the housing. The physical property data of the insulating material discloses the tensile strength but does not disclose the compressive strength. However, it is generally known that the bending strength is 1.2 to 1.4 times higher than the tensile strength. As the insulating ring material, it is desirable to use a material containing PPS + 30% glass fiber and having a tensile strength of 170 MPa or more. In the case of a material having low strength, there is a high possibility that the bolt will be loosened by causing deformation of the material. By using the insulating material as described above, it is possible to electrically insulate, and it is possible to improve the reliability of the rolling bearing with a material that is lower in cost than in the past.

  A scroll compressor according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 9 is a diagram illustrating the structure of the auxiliary bearing mounting portion A according to the second embodiment, and is an enlarged cross-sectional view of the mounting portions of the housing 133 and the lower frame 137. The points different from the first embodiment will be mainly described.

  In FIG. 9, the auxiliary bearing 105 is constituted by an inner ring 105a, an outer ring 105c, and rolling elements 105b therebetween. The outer ring 105c of the auxiliary bearing 105 is inserted into the inner peripheral surface of the housing 133, the space between the housing 133 and the lower frame 137 is bolted with a bolt 138, and an insulating sheet 190 is provided between the lower frame 137 and the bolt 138. A bush 193 with an insulating flange and a metal flat washer 192 are provided between 133 and the bolt 138 to electrically insulate the lower frame 137 and the housing 133 from each other.

  The feature of the bush 193 with an insulating rod is that the contact between the bolt 138 and the housing 133 can be completely avoided as compared with the case of the insulating ring 191. The bush 193 with an insulating flange is a modification of the insulating ring, and can be said to be a central portion of the disk-shaped insulating ring 191 and a flange formed in the height direction.

  According to the second embodiment, the insulation and the fastening force of the bolt can obtain the same effect as the first embodiment, the current to the auxiliary bearing 105 can be prevented from flowing, and the reliability of the rolling bearing can be improved. Can do.

  A scroll compressor according to Embodiment 3 of the present invention will be described with reference to FIG. FIG. 10 is a diagram illustrating the structure of the bolt fastening portion B according to the third embodiment, and is an enlarged cross-sectional view of the mounting portion of the housing 133 and the lower frame 137. The points different from the first embodiment will be mainly described.

  In FIG. 10, the auxiliary bearing 105 includes an inner ring 105 a and an outer ring 105 c and rolling elements 105 b therebetween. The outer ring 105c of the auxiliary bearing 105 is inserted into the inner peripheral surface of the housing 133, the space between the housing 133 and the lower frame 137 is bolted with a bolt 138, and an insulating sheet 190 is provided between the lower frame 137 and the bolt 138. A metal washer 192 is provided on the metal ring 194 with an oxide film layer 195 between the bolt 133 and the bolt 138 to electrically insulate the lower frame 137 and the housing 133 from each other.

  By forming an oxide film layer on the metal ring 194, deformation due to bolt fastening can be suppressed, and the fastening force between the bolt 138 and the housing 133 can be prevented from loosening due to secular change compared to the case of the insulating ring 191. Is a feature. As the oxide film layer 195, a ceramic material (alumina oxide, silicon oxide, chromium oxide, etc.) by surface modification or surface treatment is preferable. In the case of Example 3, it can be said that the insulating ring is a metal ring 194 formed with an oxide film layer.

  According to the third embodiment, the same effects as those of the first embodiment can be obtained with respect to insulation and bolt fastening force. Further, it is possible to prevent a current from flowing to the auxiliary bearing 105 and to improve the reliability of the rolling bearing. Further, creep due to aging can be prevented more than the resin system.

1: Scroll compressor 2: Compression mechanism unit 3: Drive unit 100: Sealed container 101: Rotating shaft 101a: Eccentric pin unit 101b: Main shaft unit 102: Oil supply path 102a: Oil supply path 103: Swivel bearing 104: Main bearing 105: Sub bearing 105a: inner ring 105b: rolling element 105c: outer ring 106: oil pump 107: rotor 108: stator 110: stationary scroll 110a: spiral wrap 110b: end plate 110e: discharge port 120: orbiting scroll 120a: spiral wrap 120b: End plate 120e: Boss portion 120f: Boss portion end surface 130: Compression chamber 131: Oil reservoir 133: Housing 134: Oldham joint 136: Discharge space 137: Lower frame 138: Bolt 140: Suction port 141: Key groove 150: Discharge port 160: Frame 161: Ring-shaped groove 170: Small hole 172: Seal Material 180: Back pressure chamber 181: High pressure chamber 184: Discharge passage 190: Insulating sheet 191: Insulating ring 192: Plain washer 193: Insulating bush 194: Metal ring 195: Oxide coating layer 204: Thrust bearing 210: Evaluation of fastening force Jig A: Sub-bearing mounting part B: Bolt tightening part D: External size d: Internal diameter size T: Torque F: Axial force k: Torque coefficient

Claims (6)

In a sealed container, a compression mechanism unit including a fixed scroll and a revolving scroll, an electric motor unit that drives the compression mechanism unit, and a vertical axis rotation shaft that transmits the rotational force of the electric motor unit to the compression mechanism unit, An auxiliary bearing arranged to surround the rotating shaft and supporting the rotating shaft, a housing supporting the auxiliary bearing, an oil reservoir for storing lubricating oil, and the lubricating oil in the oil reservoir being rotated An oil supply path that supplies the auxiliary bearing via a shaft, and a scroll compressor that is fixed by bolting between a lower frame fixed in the sealed container and the housing,
When bolting between the lower frame and the housing, an insulating sheet is provided between the housing and the lower frame, an insulating ring and a metal flat washer are provided between the housing and the bolt, A scroll compressor characterized in that the secondary bearing is electrically insulated. The scroll compressor according to claim 1,
As the insulating ring, a scroll compressor having a central portion of a disk-shaped insulating ring and a bush with an insulating flange formed with a flange portion in the height direction is used. The scroll compressor according to claim 1,
The scroll compressor according to claim 1, wherein the insulating ring is formed by providing an oxide film layer on a surface of a metal ring. The scroll compressor according to any one of claims 1 to 3,
A scroll compressor characterized in that the ratio of the outer diameter size D and the inner diameter size d of the metal plain washer is D / d ≧ 2. A scroll compressor according to any one of claims 1 to 4,
A scroll compressor characterized in that a tensile strength of a material of an insulating sheet provided between the housing and the lower frame is 170 MPa or more. A scroll compressor according to any one of claims 1 to 4,
A scroll compressor characterized in that a material containing at least 30% or more glass fiber in poniphenylene sulfide (PPS) or polyether ether ketone (PEEK) is used as the material of the insulating sheet.

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