JP5889142B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor, and more particularly to an improvement in the reliability of a thrust bearing slide bearing provided as a separate member on the back surface of an orbiting scroll of the scroll compressor.

  A scroll compressor includes a journal bearing that supports a main shaft that is rotated by the power of a motor, and a thrust bearing that receives pressure generated in a compression section. In general, when the compression part is composed of two spirals meshing with each other, one is fixed inside the scroll compressor as a fixed scroll, and the other is a revolving motion as a swinging scroll (revolving motion without rotation). Thus, the compression portion is formed by performing a swinging motion). The refrigerant taken into the compression unit is increased in pressure by the revolving motion of the orbiting scroll, but a load (thrust load) is generated in the direction of separating the spirals due to the pressure difference between the inside of the compression unit and the back surface of the orbiting scroll. In order to hold the load, a sliding portion is provided as a thrust bearing between the back surface of the orbiting scroll and the frame fixed inside the compressor. However, even in the case of thrust bearings, even if there is sufficient lubricating oil, the sliding strength varies greatly depending on the material of the sliding member, the roughness of the processed surface, the hardness difference between the sliding members, the ambient temperature, etc. There were problems such as abnormal wear at the sliding part and bearing seizure.

  Thus, for example, Patent Document 1 introduces a configuration that improves the reliability of the thrust bearing by separately providing a bearing material having high sliding resistance on the back side of the orbiting scroll. However, in the configuration in which only the thrust receiver is added as in Patent Document 1, relative sliding displacement occurs between the three of the swing scroll, the thrust receiver, and the frame. It was not enough to prevent bearing seizure. Further, since the thrust receiver is deformed by the pressure of the compression portion, the deformation of the thrust receiver is also a cause of promoting the phenomenon such as the above abnormal wear.

  On the other hand, in the conventional thrust bearing structure, two bolt holes are formed on the back surface of the orbiting scroll at positions substantially symmetrical with respect to the center of the base plate of the orbiting scroll to play a role in positioning the thrust receiver. There is a structure in which each reamer bolt is inserted. That is, the thrust receiver is provided with two reamer holes, one is a circular round hole shape, and the other is an oval long hole shape consisting of two semicircles and two straight portions. The longitudinal direction of the hole shape is configured to face the center direction of the thrust receiver. Then, the thrust receiver is positioned by fitting the round reamer hole with a clearance so that the head of one reamer bolt inserted into the orbiting scroll has a predetermined clearance. In addition, the rotation direction of the thrust receiver is positioned with respect to the orbiting scroll by fitting the head of the other reamer bolt into the elongated reamer hole with a predetermined clearance. Also, the bolt hole center position and reamer hole center position misalignment when the thrust receiver is attached to the back of the orbiting scroll, and the reamer bolt seating position misalignment (screw rotation position misalignment) are absorbed in a long hole shape. Therefore, the predetermined clearance in the longitudinal direction on the long hole shape side is set to be larger than the predetermined clearance on the round hole shape side.

Japanese Patent No. 4749136

However, in the structure of the conventional thrust bearing as described above, the revolving motion of the orbiting scroll during operation is such that the side surface of the reamer hole of the thrust receiver and the side surface of the head portion of the reamer bolt fitted with a clearance so as to have a predetermined clearance. In addition to repeated contact and collision due to the centrifugal force of the thrust receiver itself, the dynamic friction coefficient of the thrust bearing increases depending on the transient lubrication failure and operating conditions of the thrust bearing. Revolution while dragging causes a very large load to act, causing a problem that the head of the reamer bolt is damaged. Also, if the reamer bolt head breaks even on one side, it will not be possible to prevent rotation of the thrust receiver itself with the other fulcrum as the fulcrum. The thrust receiver itself will be damaged.
Moreover, in order to process the long hole shape of a thrust receiver, since it is necessary to run a rotary blade along a long hole shape side surface, it will increase a cost. Especially on the long hole side, the straight part and reamer bolt head, which were necessary for ensuring assembly, are in contact, collision, and high load action. However, since the surface pressure drop is slow, the reamer hole of the thrust receiver and the reamer bolt head wear abnormally, and the scroll compressor may break down due to the damage of the thrust receiver or the reamer bolt head.
Also, if all the reamer holes of the thrust receiver are to be configured in a round hole shape, the reamer hole by ensuring the above-described assemblability of the thrust receiver and having a predetermined gap while maintaining this structure. Since there is a conflict between minimizing the collision between the side surface and the reamer bolt head side surface, it is difficult to achieve both.

  The present invention has been made to solve the above-described problems, and provides a scroll compressor capable of improving the reliability of a thrust bearing while maintaining the assemblability of the thrust receiver and the number of parts. It is the purpose.

  A scroll compressor according to the present invention includes a hermetic container, a fixed scroll fixed to the hermetic container, an orbiting scroll combined to revolve with respect to the fixed scroll, and rotation drive means for revolving the orbiting scroll. Two thrust members inserted in the back surface of the orbiting scroll and two insertion member holes into which the insert members are inserted are formed, and the thrust member is disposed on the back surface of the orbiting scroll and supports the orbiting scroll. And a frame that is fixed to the hermetic container and supports the thrust receiver, the orbiting scroll has a counterbore hole in which the head of the insertion member sinks and is fixed from the back of the orbiting scroll, The two insertion member holes provided in the thrust receiver are characterized by being formed in a circular round hole shape so that the heads of the insertion members respectively fit.

In the scroll compressor according to the present invention, the orbiting scroll has a circular counterbore in which the head of the insertion member sinks and is fixed from the back surface of the orbiting scroll, and is provided with two thrust receivers. Since each insertion member hole is formed in a circular round hole shape so that the head part of the insertion member fits, the insertion member head part and the insertion member hole are all round hole shape and round hole shape. It becomes a combination. Therefore, not only can the surface pressure increase due to the contact between the straight line and the round hole as in the conventional case be avoided, but also the local surface pressure can be greatly reduced with a little wear, so that abnormal wear does not occur. Moreover, since the processing time of the insertion member hole can be shortened, the processing cost of the thrust receiver can be suppressed.
Furthermore, since the insertion member hole can be changed from a long hole shape to a round hole shape, the surplus in the longitudinal direction of the long hole shape can be increased, so that the strength of the thrust receiver against damage can be improved. In addition, since the thrust receiver rotates together with the orbiting scroll, relative sliding displacement does not occur. Therefore, the lubricating oil supplied to the thrust bearing during operation and the thrust load continuously cause the thrust receiver in the circumferential direction. The formed oil film breakage is reduced, and seizure in the thrust bearing can be improved.

It is a longitudinal section showing an example of composition of a scroll compressor concerning an embodiment of the invention. It is a perspective view which expands and shows the rocking | fluctuation scroll and thrust receiver of the scroll compressor which concerns on embodiment of this invention. It is an expanded sectional view of the reamer bolt attachment part of FIG. It is a graph which shows the result of the endurance test of the thrust bearing part of the scroll compressor concerning an embodiment of the invention compared with the conventional structure. It is the graph and conceptual diagram which show the abrasion condition of the thrust bearing part of the scroll compressor which concerns on embodiment of this invention.

  Embodiments of a scroll compressor according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing a configuration example of a scroll compressor 100 according to an embodiment of the present invention. Based on FIG. 1, the structure and operation | movement of the scroll compressor 100 are demonstrated. This scroll compressor 100 becomes one of the components of the refrigerating cycle used for various industrial machines, such as a refrigerator, a freezer, an air conditioning apparatus, a freezing apparatus, and a water heater. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

  The scroll compressor 100 sucks the refrigerant circulating in the refrigeration cycle, compresses it, and discharges it as a high-temperature and high-pressure state. This scroll compressor 100 is a compression in which a fixed scroll 1 and an orbiting scroll 2 that revolves (oscillates) with respect to the fixed scroll 1 are combined in an airtight container 24 composed of a center shell 7, an upper shell 22, and a lower shell 23. It has a mechanism. In addition, the scroll compressor 100 is provided with a rotation driving means such as a motor in the sealed container 24. As shown in FIG. 1, in the sealed container 24, the compression mechanism is disposed on the upper side, and the rotation driving means is disposed on the lower side.

  The sealed container 24 is configured by providing an upper shell 22 and a lower shell 23 on the upper and lower portions of the center shell 7. The lower shell 23 is an oil sump for storing lubricating oil. The center shell 7 is connected with a suction pipe 15 for sucking refrigerant gas. A discharge pipe 17 for discharging the refrigerant gas is connected to the upper shell 22. The inside of the center shell 7 is a low pressure chamber 18, and the inside of the upper shell 22 is a high pressure chamber 19.

  The fixed scroll 1 is composed of a fixed scroll base plate 1b and a fixed scroll spiral 1a which is a spiral projection standing on one surface of the fixed scroll base plate 1b. The orbiting scroll 2 is an orbiting scroll base plate 2b and an orbiting scroll that is provided on one surface of the orbiting scroll base plate 2b and is a spiral protrusion having substantially the same shape as the fixed scroll volute 1a. And the spiral 2a. Note that the other surface of the swing scroll base plate 2b (the surface opposite to the surface on which the swing scroll spiral 2a is formed) is a protrusion that protrudes downward from the swing scroll back surface 2c on the outer peripheral side. There is a part 2d.

  Two reamer bolts 4 are inserted in the swing scroll back surface 2c. When the scroll compressor 100 is assembled, the head of the reamer bolt 4 is inserted and positioned in the reamer hole (insertion member hole) 26 formed in the thrust receiver 3 in a state where the reamer bolt 4 is inserted into the swing scroll back surface 2c. The thrust receiver 3 is formed in a ring shape, and the convex portion 2d of the orbiting scroll 2 is located in the central portion (hereinafter referred to as the central space portion 3a for convenience). The lower surface 3b of the thrust receiver 3 is positioned below the tip surface of the convex portion 2d. The reamer bolt 4 and the thrust receiver 3 will be described in detail with reference to FIG.

  Here, the case where the reamer bolt 4 is provided on the rocking scroll back surface 2c and the reamer hole 26 is provided on the thrust receiver 3 will be described as an example. However, the insertion member hole is provided on the rocking scroll back surface 2c, and the insertion member is provided on the thrust receiver 3. May be provided. However, in order to insert and fix the insertion member in the thrust receiver 3, the thickness of the thrust receiver 3 needs to be increased to some extent.

  The orbiting scroll 2 is configured such that a thrust bearing load generated during operation of the compressor is supported by the frame 20 via the thrust receiver 3. If the frame 20 does not have sufficient hardness with respect to the thrust bearing load, a material having sufficient hardness with respect to the thrust bearing load is interposed between the thrust receiver 3 and the frame 20 as shown in FIG. It is good also as a structure which inserts the thrust plate 5 which consists.

  The orbiting scroll 2 and the fixed scroll 1 are mounted in an airtight container 24 by combining the orbiting scroll spiral 2a and the fixed scroll spiral 1a. In a state where the swing scroll 2 and the fixed scroll 1 are combined, the winding directions of the fixed scroll spiral 1a and the swing scroll spiral 2a are opposite to each other. A compression chamber 30 whose volume changes relatively is formed between the swing scroll spiral 2a and the fixed scroll spiral 1a. Note that the fixed scroll 1 and the orbiting scroll 2 have a front end surface (upper surface) of the fixed scroll swirl 1a and the orbiting scroll swirl 2a in order to reduce refrigerant leakage from the front end surfaces of the fixed scroll swirl 1a and the orbiting scroll swirl 2a. Seals 31 and 32 are disposed on the end surface and the lower end surface.

  The fixed scroll 1 is fixed to the frame 20 with bolts or the like not shown. A discharge port 16 is formed at the center of the fixed scroll base plate 1b of the fixed scroll 1 to discharge the compressed refrigerant gas having a high pressure. The compressed refrigerant gas having a high pressure is discharged into a high-pressure chamber 19 provided in the upper part of the fixed scroll 1. The refrigerant gas discharged to the high pressure chamber 19 is discharged to the refrigeration cycle via the discharge pipe 17. The discharge port 16 is provided with a discharge valve 33 for preventing the refrigerant from flowing backward from the high pressure chamber 19 to the discharge port 16 side.

  The oscillating scroll 2 performs a revolving motion (oscillating motion) without rotating about the fixed scroll 1 by an Oldham ring 14 for preventing the rotating motion. A hollow cylindrical boss 2e is formed at a substantially central portion of the surface of the swing scroll 2 opposite to the surface on which the swing scroll spiral 2a is formed. An eccentric shaft portion 8a provided at the upper end of the main shaft 8 is inserted into the boss portion 2e.

  The Oldham ring 14 is installed such that the Oldham claw is accommodated in the Oldham groove (Oldham groove 6a shown in FIG. 2) formed in the convex portion 2d of the swing scroll 2 and the back surface 2c of the swing scroll. The thrust receiver 3 is provided with an Oldham ring relief groove 6b. The Oldham ring relief groove 6b is formed in order to avoid interference with the Oldham groove 6a formed on the swing scroll thrust bearing surface 2c. The Oldham ring 14 may be installed on the surface of the swing scroll base plate 2b on which the swing scroll spiral 2a is formed.

  The rotation driving means includes a rotor 11 fixed to the main shaft 8, a stator 10, a main shaft 8 that is a rotation shaft, and the like. The rotor 11 is shrink-fitted and fixed to the main shaft 8 and is driven to rotate when the energization of the stator 10 is started to rotate the main shaft 8. That is, the stator 10 and the rotor 11 constitute a motor. The rotor 11 is disposed below the first balance weight 12 that is fixed to the main shaft 8 together with the stator 10 that is shrink-fitted and fixed to the center shell 7. The stator 10 is supplied with power via a power supply terminal 9 provided in the center shell 7.

  The main shaft 8 rotates with the rotation of the rotor 11 to turn the orbiting scroll 2. The upper portion of the main shaft 8 (in the vicinity of the eccentric shaft portion 8a) is supported by a main bearing 21 provided on the frame 20. On the other hand, the lower portion of the main shaft 8 is rotatably supported by the auxiliary bearing 35. The sub-bearing 35 is press-fitted and fixed in a bearing housing portion formed at the center of a sub-frame 34 provided at the lower part of the sealed container 24. A positive displacement oil pump 25 is attached to the lower end of the main shaft 8. The lubricating oil sucked by the oil pump 25 is sent to each sliding portion through an oil hole (not shown) formed inside the main shaft 8.

  In addition, a first balance weight 12 is provided on the upper portion of the main shaft 8 in order to cancel out an unbalance caused by the swing scroll 2 being mounted on the eccentric shaft portion 8a and swinging. A second balance weight 13 is provided at the lower part of the rotor 11 in order to cancel out imbalance caused by the swing scroll 2 being mounted on the eccentric shaft portion 8a and swinging. The first balance weight 12 is fixed to the upper part of the main shaft 8 by shrink fitting, and the second balance weight 13 is fixed to the lower part of the rotor 11 integrally with the rotor 11.

Next, the operation of the scroll compressor 100 will be described.
When the power supply terminal 9 is energized, a current flows through the electric wire portion of the stator 10 and a magnetic field is generated. This magnetic field acts to rotate the rotor 11. That is, torque is generated in the stator 10 and the rotor 11, and the rotor 11 rotates. When the rotor 11 rotates, the main shaft 8 is rotationally driven accordingly. When the main shaft 8 is driven to rotate, the orbiting scroll 2 whose rotation is suppressed by the Oldham ring 14 performs a revolving motion.

  When the rotor 11 rotates, the swing scroll 2 and the thrust receiver 3 are composed of a first balance weight 12 fixed to the upper part of the main shaft 8 and a second balance weight 13 fixed to the lower part of the rotor 11. Maintains a static and dynamic balance with respect to the eccentric revolving motion. As a result, the swinging scroll 2 that is eccentrically supported on the upper portion of the main shaft 8 and whose rotation is suppressed by the Oldham ring 14 is swung to start a revolving motion, and compresses the refrigerant by a known compression principle.

  As a result, part of the refrigerant gas flows into the compression chamber 30 via the suction port (not shown) of the frame 20, and the suction process is started. Further, the remaining part of the refrigerant gas cools the motor and the lubricating oil through a notch passage (not shown) of the steel plate of the stator 10. The compression chamber 30 moves to the center of the orbiting scroll 2 by the revolving motion of the orbiting scroll 2, and the volume is further reduced. Through this process, the refrigerant gas sucked into the compression chamber 30 is compressed. The compressed refrigerant passes through the discharge port 16 of the fixed scroll 1, pushes the discharge valve 33 open, and flows into the high-pressure chamber 19. Then, it is discharged from the sealed container 24 through the discharge pipe 17. In this way, the scroll compressor 100 continuously repeats refrigerant gas suction → compression → discharge.

  The thrust bearing load generated by the pressure of the refrigerant gas in the compression chamber 30 is received by the frame 20 that supports the thrust receiver 3. The reamer bolt 4 supports the resultant force of the frictional force between the thrust receiver 3 and the frame 20 generated by the thrust bearing load and the centrifugal force of the thrust receiver 3. Further, the main bearing 21 and the sub-bearing 35 receive the centrifugal force and the refrigerant gas load generated in the first balance weight 12 and the second balance weight 13 as the main shaft 8 rotates. Note that the low-pressure refrigerant gas in the low-pressure chamber 18 and the high-pressure refrigerant gas in the high-pressure chamber 19 are partitioned by the fixed scroll 1 and the frame 20 and are kept airtight. When the energization of the stator 10 is stopped, the scroll compressor 100 stops operating.

FIG. 2 is an enlarged perspective view showing the orbiting scroll 2 and the thrust receiver 3 of the scroll compressor 100 according to the embodiment of the present invention. FIG. 3 is an enlarged cross-sectional view of the reamer bolt 4 mounting portion of FIG.
Two bolt holes 28 having counterbore holes 27 are provided on the orbiting scroll back surface 2 c at positions substantially symmetrical with respect to the center of the orbiting scroll 2. Reamer bolts 4 are inserted into the bolt holes 28, respectively. At this time, the head 4a of the reamer bolt 4 is formed in a circular shape with a high accuracy in outer diameter, and a part (root part) of the head 4a sinks into the counterbore 27, and the remaining part ( The lower part protrudes from the rocking scroll back surface 2c. Although not shown, the head portion 4a of the reamer bolt 4 is provided with a tool engaging portion such as a hexagon hole for fastening the reamer bolt 4.
On the other hand, in order to improve the slidability with respect to the frame 20 fixed in the hermetic container 24, a space including a concave portion for accommodating the thrust receiver 3 is provided on the back surface of the orbiting scroll 2. Further, the thrust receiver 3 is formed with a reamer hole 26 that is reamed into a circular round hole shape so that the head 4a of each reamer bolt 4 is fitted with a clearance fit.

  By the way, a large load is generated in the orbiting scroll 2 during operation of the compressor in the direction in which the compression chamber 30 is opened (enlarged) by the compressed refrigerant gas, that is, in the direction in which the orbiting scroll 2 is pressed against the frame 20. The thrust load is supported by the frame 20 via a thrust receiver 3 provided on the rocking scroll back surface 2c. Therefore, a sliding portion called a thrust bearing is formed between the lower surface 3b of the thrust receiver 3 and the frame 20, and the thrust bearing is configured by sliding with lubricating oil. A thrust receiver 3 and a plate with good sliding characteristics (for example, the thrust plate 5 in FIG. 1) may be provided on the frame 20 side.

However, unlike the prior art, no counterbore 27 is provided on the back surface of the orbiting scroll 2, the head 4a of the reamer bolt 4 does not sink into the back surface of the orbiting scroll 2, and the entire head 4a remains protruding. In this configuration, there were problems as described above. That is, the orbiting scroll 2 does not revolve in a stable posture due to the centrifugal force fluctuation of the orbiting scroll swirl 2a due to the increase / decrease of the motor or the frequent fluctuation of the suction pressure or the discharge pressure due to the load fluctuation on the unit side such as an air conditioner. . Therefore, in the thrust bearing, a large load is applied to the thrust receiver 3 due to the occurrence of an oil film breakage even when sufficient lubricating oil is supplied, or due to repeated increase in frictional force due to a temporary increase in thrust load. It is working.
Therefore, when the thrust receiver 3 is dragged, the collision between the head 4a of the reamer bolt 4 holding the thrust receiver 3 and the reamer hole 26 of the thrust receiver 3 and a high-load sliding are performed. The head 4a of the reamer bolt 4 or the thrust receiver 3 itself may be damaged, and as a result, the scroll compressor may break down.

As a method of holding the thrust receiver 3 on the rocking scroll back surface 2c, in the case of a conventional combination of a round hole shape and a long hole shape, the gap size required in the longitudinal direction of the long hole shape is from the following (1) to (4 ) Of the dimensional error.
(1) Variation in processing at the center of the bolt hole 28 on the back of the orbiting scroll 2 (2) Variation in seating position when the reamer bolt 4 is fastened to the bolt hole 28 (3) Center of the head 4a and the screw portion 4b of the reamer bolt 4 itself Position variation (4) Predetermined clearance that allows the reamer hole 26 of the thrust receiver 3 and the head 4a of the reamer bolt 4 to be fitted into a gap (1), (3) is determined by the processing accuracy at the time of manufacture, but the variation is minimized. Even so, the target value of about ± 30 microns and (4) of up to about a dozen microns are general limits when considering mass productivity. However, (2) is a fit between the screw part 4b of the reamer bolt 4 and the bolt hole 28 part of the orbiting scroll 2. For example, even in the JIS standard of M5 bolt, a general fit tolerance is 0.376 mm at the maximum and the center value. Since the tolerance is usually one order of magnitude as large as 0.2 mm, it is necessary to have a longitudinal gap dimension capable of absorbing the total of them.

Therefore, a counterbore hole 27 that is concentric with the center of the bolt hole 28 of the orbiting scroll 2 and slightly larger than the outer diameter (reamer bolt head diameter) of the head 4a of the reamer bolt 4 is provided. Then, a part of the head 4a of the reamer bolt 4 is sunk into the counterbore 27 and fastened with the side surface of the counterbore 27 provided in the swing scroll 2 as a guide. At that time, if the backlash of the screw part fit> (counterbore hole diameter−reamer bolt head diameter), it is possible to sit down to the bottom of the counterbore hole 27 in a so-called hand-tight state before applying torque to the reamer bolt 4. . In this state, when the reamer bolt 4 is tightened with the specified torque, the reamer bolt 4 slides so as to follow the fitting center of the screw portion 4b, but stops when the head 4a comes into contact with the side surface of the counterbore hole 27. Can be applied to reamer bolt 4.
Generally, a bolt that is fastened is a mechanism that balances the reaction force of the seating surface and the screw portion 4b to maintain torque. In this structure, most of the torque is seated in the same way as a generally fastened bolt. It is held by the reaction force of the surface and the screw portion, and only a part of the torque is held by the bolt head side surface and the counterbore side surface, and there is no significant difference in the overall holding torque. From the above, the seating position shift of the reamer bolt 4 can be surely suppressed within the inner diameter of the counterbore 27 while maintaining the necessary holding torque.

Moreover, in order to make a combination of a round hole shape and a round hole shape with a conventional structure, when assembling the parts (1) to (4) is considered, when the reamer bolt 4 is fitted into the reamer hole 26 with a gap, Both of the predetermined clearances need to be set larger by one order than the combination of the round hole shape and the long hole shape.
If the predetermined clearance is set large, the assemblability can be solved, but the contact around the thrust receiver 3 during operation due to the predetermined clearance becomes large, and there is a high possibility of interference with other parts. Further, the centrifugal force of the thrust receiver 3 itself and the revolving motion of the orbiting scroll 2 repeat the reciprocating motion and the collision between the predetermined clearances with the one reamer hole 26 as a fulcrum. Normally, the reciprocating scroll 2 makes one reciprocation between predetermined clearances during one rotation. In particular, since the collision energy is proportional to the square of the driving speed under the condition where the driving frequency is high, there is a problem that increasing the predetermined clearance leads to damage to the thrust receiver 3 or the head 4a of the reamer bolt 4.

FIG. 4 is a graph showing a result of a durability test of the thrust bearing portion of the scroll compressor 100 according to the embodiment of the present invention in comparison with a conventional structure. In FIG. 4, the horizontal axis represents the predetermined clearance (mm) between the reamer bolt head and the reamer hole of the thrust receiver, and the vertical axis represents the clearance expansion amount (mm), that is, the wear amount (mm). A graph A indicated by a dotted line is based on a combination of the round hole shape and the long hole shape of the conventional structure, and a graph B indicated by a solid line is based on a combination of the round hole shape and the round hole shape of the present embodiment.
From FIG. 4, according to the thrust bearing according to the combination of the round hole shape and the round hole shape of the present embodiment, the clearance expansion amount is much smaller than that according to the combination of the round hole shape and the long hole shape of the conventional structure. I understand that.
Further, in the present embodiment, when the assemblability of the thrust receiver is also considered, the predetermined clearance between the reamer hole of the thrust receiver and the reamer bolt head is preferably around 0.10 mm, and is in the range of 0.05 to 0.15 mm. It would be good if.

  In the present embodiment, the following countermeasures are taken against damage to the head 4a of the reamer bolt 4. That is, a part of the head 4 a of the reamer bolt 4 is submerged in the counterbore 27. This is to prevent the counterbore 27 from coming out even if the head 4a is damaged. In the present embodiment, the increased amount of contact around the thrust receiver 3 is only the difference between the counterbore 27 and the reamer bolt head diameter, and the reliability is not greatly impaired. Therefore, if the thickness of the head 4a of the reamer bolt 4 is set to be larger than the total amount of the thickness of the thrust receiver 3 and the tooth gap of the orbiting scroll 2 and the fixed scroll 1, the head of the reamer bolt 4 4a does not exit the counterbore 27. That is, by making the fitting depth of the reamer bolt 4 to the reamer hole 26 of the head 4a and the thickness of the thrust receiver 3 equal, even if the head 4a of the reamer bolt 4 is damaged, the head 4a Both holes 27 and reamer holes 26 are engaged. For this reason, since the thrust receiver 3 rotates together with the orbiting scroll 2, there is almost no relative sliding deviation between them, so that not only can the thrust receiver itself be damaged, but also abnormal wear on the thrust bearing. And bearing seizure can be reduced.

FIG. 5 is a graph and a conceptual diagram showing the wear state of the thrust bearing portion of the scroll compressor 100 according to the embodiment of the present invention in comparison with the conventional structure. In the graph of FIG. 5, the horizontal axis represents the enlargement amount δ (μm), and the vertical axis represents the projection length L (μm) shown in the following figure.
Graph A is based on the combination of the conventional round hole shape (φ8 mm) and the long hole shape, and graphs B and C are based on the combination of the round hole shape and the round hole shape of the present embodiment. Graph B shows a combination of reamer hole diameter (φ8.1 mm) and reamer bolt head diameter (φ8.01 mm), and graph C shows a combination of reamer hole diameter (φ8 mm) and reamer bolt head diameter (φ7.75 mm). Both clearances are 0.09 mm and 0.25 mm, respectively.

As can be seen from FIG. 5, according to the present embodiment, the combination of the round hole shape and the round hole shape is effective in the following points as compared to the conventional combination of the long hole shape and the round hole shape.
(1) In the case of the contact combination of the long hole and the reamer bolt head, it is a contact between a straight line and a circle, which is close to a point and the contact surface pressure becomes very high. Since the contact with the surface is approached, the contact surface pressure can be reduced.
(2) When a slight amount of wear has progressed, a combination of a straight line and a circle slows down the contact pressure because the contact area increases slowly and the progress of wear does not stop. However, in the case of a combination of a circle and a circle, the contact area increases rapidly, so the surface pressure decreases rapidly and the progress of wear can be greatly suppressed.

  DESCRIPTION OF SYMBOLS 1 Fixed scroll, 1a Fixed scroll swirl, 1b Fixed scroll base plate, 2 Swing scroll, 2a Swing scroll swirl, 2b Swing scroll base plate, 2c Swing scroll back surface, 2d Convex part, 2e Boss part, 3 Thrust receiving 3a Center space part, 3b Thrust receiving lower surface, 4 Reamer bolt, 4a Head, 4b Screw part, 5 Thrust plate, 6 Oldham groove, 6a Oldham groove, 6b Oldham ring relief groove, 7 Center shell, 8 Main shaft, 8a Eccentric shaft , 9 power terminal, 10 stator, 11 rotor, 12 first balance weight, 13 second balance weight, 14 Oldham ring, 15 suction pipe, 16 discharge port, 17 discharge pipe, 18 low pressure chamber, 19 high pressure chamber, 20 frame, 21 main bearing, 22 upper shell, 23 lower 24, closed container, 25 oil pump, 26 reamer hole, 27 counterbore hole, 28 bolt hole, 30 compression chamber, 31 seal, 32 seal, 33 discharge valve, 34 subframe, 35 secondary bearing, 100 scroll compressor .

Claims (2)

A sealed container;
A fixed scroll fixed to the sealed container;
An orbiting scroll combined to revolve with respect to the fixed scroll;
Rotation drive means for revolving the swing scroll;
Two insertion members inserted into the back of the rocking scroll;
Two insertion member holes into which the insertion member is inserted are formed, and a thrust receiver that is disposed on the back surface of the orbiting scroll and supports the orbiting scroll;
A frame fixed to the sealed container and supporting the thrust receiver;
With
The orbiting scroll has a circular counterbore hole in which the head of the insertion member sinks and is fixed from the back of the orbiting scroll,
The scroll compressor characterized in that the two insertion member holes provided in the thrust receiver are formed in a circular round hole shape so that the heads of the insertion members are respectively fitted. The scroll compressor according to claim 1, wherein a fitting depth of a head of the insertion member in the insertion member hole of the thrust receiver is substantially equal to a thickness of the thrust receiver.

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