JP2010229883A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll compressor capable of supporting a radial load and a thrust load simultaneously by adopting a conical bearing to an auxiliary bearing and securing long-term reliability. <P>SOLUTION: In the scroll compressor 100, an auxiliary bearing 11 has an approximately conical bearing part 11', and an auxiliary shaft 6c approximately in a conical shape is supported by the conical bearing part 11'. In inclined dynamic pressure surfaces of the auxiliary shaft 6c and the bearing part 11', an open angle θ1 formed between a pair of bus bars on the sliding surface of the auxiliary shaft 6c is set smaller than an open angle θ2 formed between a pair of bus bars on the sliding surface of the bearing part 11' in which the bearing part 11' and the auxiliary shaft 6c plane-contact with each other in a state that the main shaft 6 is stopped in rotation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a scroll compressor used as one of components of a refrigeration cycle apparatus.

  A scroll compressor used as one of the components of a refrigeration cycle apparatus such as an air conditioner is provided with a shaft (main shaft) for revolving a rocking scroll of a compression mechanism, and the shaft is provided above and below the electric motor. In general, the main bearing and the auxiliary bearing are supported. That is, the shaft supported by the main bearing and the sub-bearing is rotationally driven by the electric motor, and the swing scroll attached to the eccentric shaft at the tip of the shaft revolves to compress the refrigerant by the compression mechanism. ing. When the refrigerant is compressed by the compression mechanism, a radial gas load acts on the shaft.

  Further, the sub-bearing provided on the lower side of the electric motor supports the rotation of the shaft and also supports the weight of the shaft vertically downward. In such a scroll compressor, a ball bearing is often used as a secondary bearing for the purpose of simultaneously supporting both a radial load (radial load) and a thrust load (thrust load). (For example, refer to Patent Document 1). However, ball bearings have various problems such as high cost and poor long-term reliability.

  As a countermeasure, it has been studied to employ a slide bearing as a secondary bearing of the scroll compressor. A conical bearing is mentioned as a slide bearing which can support a radial load and a thrust load simultaneously. In this conical bearing, a shaft having an inclined dynamic pressure surface having a substantially conical shape is inserted into a bearing having an inclined dynamic pressure surface having a substantially conical shape so as to be relatively rotatable, and the inclined dynamic pressure surfaces of the shafts, A substantially conical inclined bearing space is formed in the clearance between the bearing and the inclined dynamic pressure surface, and the inclined bearing space is filled with a lubricating fluid (for example, see Patent Document 2).

Japanese Patent Laid-Open No. 04-241786 (page 3, FIG. 2) Japanese Patent Laying-Open No. 2005-3172 (page 4, FIG. 2)

  Generally, since a large load acts on the shaft of the scroll compressor in the radial direction, the shaft is deflected. When the shaft is deflected, the shaft is inclined and rotated in the bearing. When the rotation of the shaft is supported by a ball bearing, the clearance between the ball and the inner ring, the clearance between the ball and the outer ring absorbs the inclination of the shaft and can support the rotation of the shaft. However, it does not solve the problem of the ball bearing as described above. In addition, when a conical bearing is employed, if the shaft and the bearing are rigid bodies, there is a concern that the shaft is inclined and a piece of contact occurs and seizure occurs. Further, when the shaft is stopped, the shaft may sink into the bearing, and a twist may occur at the time of start-up, leading to seizure.

  The present invention has been made to solve the above-described problems. A conical bearing is adopted as a secondary bearing, and it is possible to support a radial load and a thrust load at the same time, and long-term reliability. An object of the present invention is to provide a scroll compressor that secures the above.

  The scroll compressor according to the present invention includes a compression mechanism unit that compresses a refrigerant, a drive mechanism unit that drives the compression mechanism unit, a main shaft that transmits a driving force of the drive mechanism unit to the compression mechanism unit, and the drive A main bearing that is provided on one side of the mechanism portion and rotatably supports the main shaft; and a sub-bearing that is provided on the other side of the drive mechanism portion and rotatably supports the tip end portion of the main shaft. The sub-bearing has a substantially conical bearing portion, and is configured to support the tip portion of the spindle that is also substantially conical with the bearing portion, and between the tip portion of the spindle and the bearing portion. In the inclined dynamic pressure surface, the opening angle formed between the pair of bus bars on the sliding surface of the tip end portion of the main shaft is larger than the opening angle formed between the pair of bus bars on the sliding surface of the bearing portion. Is set to have a small angle, and the main axis is In a state that stops rolling, characterized in that the tip portion of the main shaft and the bearing portion is in surface contact.

  According to the scroll compressor of the present invention, a conical bearing is adopted as a secondary bearing, and it is possible to support a radial load and a thrust load at the same time, with an opening angle of the bearing portion and an opening angle of the tip end portion of the main shaft. By adopting a structure with a difference, when rotating with the tip portion inclined, the tip portion and the sliding surface of the bearing portion are parallel to each other, and the tip portion touches the sliding surface of the bearing portion. Therefore, good rotation can be continued and reliability is improved. Further, during the stop, since the tip end portion of the main shaft and the bearing portion are in surface contact with each other at a part of the inclined dynamic pressure surface, the contact surface pressure can be remarkably suppressed as compared with the line contact state.

2 is a longitudinal sectional view schematically showing a cross-sectional configuration of the scroll compressor according to Embodiment 1. FIG. It is a schematic diagram which expands and shows the subbearing part of a scroll compressor. It is a schematic diagram which expands and shows the subbearing part in the state which the main axis | shaft inclines and rotates. It is a schematic diagram which expands and shows the subbearing part in the state which the main shaft has stopped rotation. FIG. 5 is a schematic diagram illustrating an enlarged sub bearing portion of a scroll compressor according to a second embodiment. 6 is an enlarged schematic diagram illustrating a sub-bearing portion of a scroll compressor according to Embodiment 3. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a longitudinal sectional view schematically showing a sectional configuration of a scroll compressor 100 according to Embodiment 1 of the present invention. Based on FIG. 1, the structure and operation | movement of the scroll compressor 100 are demonstrated. The scroll compressor 100 is mounted as one of refrigeration equipment constituting a refrigeration cycle apparatus such as a refrigerator, a freezer, a vending machine, an air conditioner, a refrigeration apparatus, or 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. Further, the thrust load is represented by an arrow a, and the radial load is represented by an arrow b.

  The scroll compressor 100 includes a compression mechanism portion A and a drive mechanism portion B that are accommodated in the sealed container 13. As shown in FIG. 1, the compression mechanism part A is disposed on the upper side of the sealed container 13, and the drive mechanism part B is disposed on the lower side of the sealed container 13. Then, the refrigerant is compressed by the compression mechanism A via the main shaft 6 that is rotationally driven by the drive mechanism B. In addition, a refrigerant suction pipe 15 for sucking a refrigerant and a refrigerant discharge pipe 16 for discharging the refrigerant are connected to the sealed container 13. The sealed container 13 is a pressure container and forms an outer shell of the scroll compressor 100. The bottom of the sealed container 13 is an oil sump 14 for storing lubricating oil (not shown).

[Compression mechanism part A]
The compression mechanism A has a function of compressing the refrigerant sucked from the refrigerant suction pipe 15 and discharging the refrigerant to the outside of the sealed container 13 through the discharge port 4 and the refrigerant discharge pipe 16. The compression mechanism part A is mainly composed of a fixed scroll 1, an orbiting scroll 2, an Oldham joint 12, and an upper housing 8a. The fixed scroll 1 includes a base plate and spiral protrusions provided on the bottom surface of the base plate. The fixed scroll 1 is fixed at the upper end portion of the upper housing 8 a fixed to the inner surface of the side wall of the hermetic container 13. The fixed scroll 1 is preferably fixed with a fastening member such as a bolt.

  As with the fixed scroll 1, the orbiting scroll 2 is also composed of a base plate and spiral protrusions provided on the top surface of the base plate. An eccentric hole to which an eccentric shaft 6 a provided at the upper end of the main shaft 6 is connected is formed in the vicinity of the center below the bottom surface of the base plate of the orbiting scroll 2. The orbiting scroll 2 performs a revolving motion without rotating about the fixed scroll 1. The orbiting scroll 2 is configured to perform a revolving motion by preventing the orbiting scroll 2 from rotating by an Oldham coupling 12 provided between the orbiting scroll 2 and the upper housing 8a.

  The fixed scroll 1 and the orbiting scroll 2 are provided so that their spiral protrusions mesh with each other. And the compression chamber 5 from which a volume changes relatively is formed by the mutual mesh | engagement of a spiral protrusion. Accordingly, the refrigerant sucked into the sealed container 13 flows from the suction port 3 formed on the outer peripheral side of the compression chamber 5, is compressed in the compression chamber 5, and is a discharge port formed at the center of the fixed scroll 1. It comes to flow out of 4. A thrust bearing 18 is provided on the lower surface side of the orbiting scroll 2, that is, between the orbiting scroll 2 and the upper housing 8a.

  The upper housing 8a is configured to fix the fixed scroll 1 at the upper end thereof and to support the orbiting scroll 2 through a thrust bearing 18 so as to be slidable from below. Further, a through hole through which the main shaft 6 passes is formed near the center of the upper housing 8a. A main bearing 19 is provided in the through hole of the upper housing 8a. In other words, the upper housing 8 a also has a function of rotatably supporting the main shaft 6 via the main bearing 19. The main bearing 19 is configured to rotatably support the main shaft 6.

[Drive mechanism B]
The drive mechanism B has a function of driving the orbiting scroll 2 in order to compress the refrigerant by the compression mechanism A. The drive mechanism B is mainly configured by a rotor 10a and a stator 10b. The rotor 10a and the stator 10b constitute an electric motor 10. The rotor 10a is fixed to the peripheral surface of the main shaft 6, and is driven to rotate when energization to the stator 10b is started. The stator 10b is fixed to the inner peripheral surface of the sealed container 13 by shrink fitting or the like, surrounds the rotor 10a through a gap, and rotates the rotor 10a.

[Other configurations]
The main shaft 6 has a function of transmitting the driving force of the driving mechanism B to the compression mechanism A. An eccentric shaft 6 a is provided at the upper end of the main shaft 6 so as to be eccentric with respect to the center of the main shaft 6. The eccentric shaft 6a is slidably connected to an oscillating bearing 17 that is press-fitted into an eccentric hole provided in the oscillating scroll 2. A balancer 6b is projected from a position above the main shaft 6 and below the eccentric shaft 6a. Further, an oil supply hole 7a is formed in the main shaft 6 so as to penetrate in the axial direction.

  A pump 7 b is provided at the lower end of the main shaft 6. The pump 7 b is provided such that the upper end opening is fitted to the lower end portion of the main shaft 6, and the lower end opening is immersed in the lubricating oil in the oil sump 14. The oil supply mechanism 7 is constituted by the pump 7b and the oil supply hole 7a formed through the main shaft 6. The oil supply mechanism 7 sucks up the lubricating oil stored in the oil reservoir 14 by the pump 7b, and the compression mechanism portion A (especially various bearings (sub bearing 11, main bearing 19, swing bearing 17, and , The thrust bearing 18) and the sliding part of the Oldham coupling 12) have a function of supplying oil.

  In the sealed container 13, a housing 8 composed of the above-described upper housing 8a and lower housing 8b is provided. The upper housing 8a functions to fix the fixed scroll 1 and to support the orbiting scroll 2 as described above. The lower housing 8 b is fixed to the inner surface of the side wall of the sealed container 13, and has a function of rotatably supporting the main shaft 6 via the auxiliary bearing 11. The above-described electric motor 10 is installed between the upper housing 8a and the lower housing 8b. The auxiliary bearing 11 is configured to rotatably support the tip end portion of the main shaft 6, and details will be described in the lower part.

  Further, the upper housing 8a and the stator 10b are formed with oil return holes 9 penetrating from the lower surface side of the orbiting scroll 2 to the lower side in the axial direction of the main shaft 6. The oil return hole 9 has a function of returning the lubricating oil used in the compression mechanism portion A to the oil sump 14. In addition, in FIG. 1, although the case where only the oil return hole 9 is formed in one side surface of the airtight container 13 is shown as an example, it is not limited to this. For example, two or more oil return holes 9 may be formed. Further, the oil return hole 9 may be formed by providing a notch in a part of the stator 10b.

  As described above, the scroll compressor 100 has the compression mechanism portion A disposed in the upper portion of the hermetic container 13 and the drive mechanism portion B disposed in the lower portion, and the driving force of the drive mechanism portion B is transmitted via the main shaft 6 to the compression mechanism portion. A is transmitted to the swing scroll 2 of A, and the swing scroll 2 is rotationally driven. In addition, the kind of lubricating oil is not specifically limited, What is necessary is just to be used as lubricating oil of the compression mechanism part A. For example, PAG (polyalkylene glycol) or the like may be used as the lubricating oil. Also, the type of refrigerant is not particularly limited.

The operation of the scroll compressor 100 will be described.
When energization is started to the stator 10b constituting the electric motor 10, the main shaft 6 starts rotating together with the rotor 10a. When the main shaft 6 starts to rotate, the orbiting scroll 2 connected to the eccentric shaft 6 a performs a revolving motion while being prevented from rotating by the Oldham joint 12. As a result, the compression chamber 5 formed by the combination of the orbiting scroll 2 and the respective spiral protrusions of the fixed scroll 1 moves toward the center while gradually reducing the volume. Therefore, the refrigerant sucked into the compression chamber 5 from the suction port 3 gradually increases its pressure, is discharged outside the apparatus through the discharge port 4 and the refrigerant discharge pipe 16, and enters the refrigerant pipe connected to the refrigerant discharge pipe 16. Pumped.

  Since the refrigerant in the sealed container 13 is discharged to the outside in this way, the inside of the sealed container 13 has a negative pressure, and the refrigerant from the refrigerant pipe outside the machine is sucked into the sealed container 13 through the refrigerant suction pipe 15. become. The refrigerant sucked into the sealed container 13 is sucked into the compression chamber 5 from the suction port 3 after cooling the electric motor 10. Further, the lubricating oil in the oil sump 14 is sent to the upper end portion of the main shaft 6 through the oil supply hole 7 a by the pump action of the oil supply mechanism 7 to lubricate the sub bearing 11, the main bearing 19, and the rocking bearing 17. Lubricating oil that has passed through the rocking bearing 17 is supplied to the thrust bearing 18 and the Oldham coupling 12 to lubricate these sliding portions. Further, the lubricating oil supplied to the Oldham coupling 12 is returned to the oil sump 14 through the oil return hole 9.

  As the scroll compressor 100 operates, both the radial load and the thrust load act on the auxiliary bearing 11. That is, the weight of the main shaft 6 acts on the auxiliary bearing 11 in the scroll compressor 100 vertically downward, and a fluctuating load synchronized with the rotation of the main shaft 6 acts in the radial direction. Therefore, the auxiliary bearing 11 of the scroll compressor 100 can simultaneously support these radial loads and thrust loads, and can ensure long-term reliability and suppress the seizure of the bearings. At the same time, it has stable and good startability.

  FIG. 2 is an enlarged schematic view showing the auxiliary bearing 11 portion of the scroll compressor 100. FIG. 3 is an enlarged schematic view showing the sub-bearing 11 portion in a state where the main shaft 6 is inclined and rotating. FIG. 4 is an enlarged schematic view showing the sub-bearing 11 portion in a state in which the main shaft 6 is stopped rotating. Based on FIGS. 2-4, the sub bearing 11 which is the characterizing part of Embodiment 1 is demonstrated in detail. As described above, the auxiliary bearing 11 rotatably supports the tip end portion of the main shaft 6. In the following description, a portion (lower end portion of the main shaft 6) supported by the sub bearing 11 of the main shaft 6 is referred to as a sub shaft 6c, and a portion supporting the sub shaft 6c is referred to as a bearing portion 11 '. In FIG. 3, the radial load acting on the sub bearing 11 is represented as Wr, and the thrust load acting on the sub bearing 11 is represented as Wt.

  The auxiliary shaft 6c has a substantially conical shape with a diameter decreasing toward the tip, and has a barrel shape in which the central portion is slightly bulged. This barrel shape is called a crowning shape. Further, the support portion of the auxiliary shaft 6c of the auxiliary bearing 11, that is, the bearing portion 11 'also has a substantially conical shape whose diameter is reduced toward the lower side in the vertical direction. As shown in FIG. 2, an opening angle formed between a pair of bus bars formed by connecting both ends of the sub shaft 6c is defined as θ1. Also, let R be the radius of curvature of the crowning shape. Further, an opening angle formed between the pair of bus bars on the sliding surface of the bearing portion 11 ′ is θ2.

The sleeve 20 will be described.
A sleeve 20 is provided between the countershaft 6c and the sliding surface of the bearing portion 11 ′. The sleeve 20 is fixed to the auxiliary shaft 6c with a pin 21 so as not to rotate relative to the auxiliary shaft 6c. A weight 22 is provided inside the sleeve 20 at a position shifted by approximately 180 ° from the position fixed by the pin 21. The opening angle formed between the pair of bus bars on the inner peripheral surface of the sleeve 20 is set to the same value θ1 as the opening angle formed between the pair of bus bars formed by connecting both ends of the auxiliary shaft 6c. ing. The outer peripheral surface of the sleeve 20 is parallel to the inner peripheral surface. Therefore, the opening angle formed between the pair of bus bars on the outer peripheral surface of the sleeve 20 is also set to θ1.

βは、副軸受１１における副軸６ｃの傾きα（副軸受１１中で副軸６ｃの軸線が垂線に対してなす傾き）と等しくなるように設定する。 The countershaft 6c and the sleeve 20 are fixed via a pin 21 in the rotational direction of the main shaft 6, and can tilt around an axis perpendicular to the paper surface along the crowning shape of the countershaft 6c. . In the auxiliary bearing 11, θ1 <θ2 is set. Further, the half value of the difference between the opening angle θ2 of the bearing portion 11 ′ and the opening angle θ1 of the countershaft 6c is β, and is expressed by the following formula (1).

β is set to be equal to the inclination α of the auxiliary shaft 6c in the auxiliary bearing 11 (the inclination formed by the axis of the auxiliary shaft 6c with respect to the perpendicular in the auxiliary bearing 11).

  As described above, in the scroll compressor 100, the auxiliary bearing 11 is structured such that the difference between the opening angle θ2 of the bearing portion 11 ′ and the opening angle θ1 of the sleeve 20 causes the auxiliary shaft 6c to be inclined. , The sleeve 20 and the sliding surface of the bearing portion 11 ′ are parallel to each other (see FIG. 3), and the auxiliary shaft 6c does not hit the sliding surface of the bearing portion 11 ′. For this reason, even if the auxiliary shaft 6c rotates in an inclined state, it is possible to continue good rotation.

The setting of the opening angle θ2 of the bearing portion 11 ′ will be described.
The thrust load Wt shown in FIG. 3 is the sum of the own weights of the main shaft 6, the balancer 6b, and the rotor 10a, and the radial load Wr is a load acting on the main shaft 6 from the swing bearing 17 and the main bearing 19 and the sub bearing 11. It is calculated by distributing to. Due to the load acting on the main shaft 6 from the rocking bearing 17, the main shaft 6 is bent. At this time, it is assumed that the auxiliary shaft 6c rotates in the auxiliary bearing 11 while being inclined by α with respect to the perpendicular.

However, since the inclination α of the counter shaft 6c is sufficiently small with respect to the half value of the opening angle θ2 of the bearing portion 11 ′, it can be approximated to zero. At this time, since the load to be supported by the auxiliary bearing 11 is Wr in the radial direction and Wt in the thrust direction, the half value of the opening angle θ2 of the bearing portion 11 ′ can be expressed by the following formula (2).

  Further, a weight 22 is provided inside the sleeve 20 at a position shifted by 180 ° from the position fixed by the pin 21 of the sleeve 20. Therefore, when the operation of the scroll compressor 100 is stopped, the sleeve 20 in the auxiliary bearing 11 is tilted toward the weight 22 and stopped (see FIG. 4). That is, in a state where the main shaft 6 is stopped rotating, the sleeve 20 is fixed to the auxiliary shaft 6c by the pin 21, and therefore, the sleeve 20 is inclined to the weight 22 side through the pin 21.

  At this time, the contact surface (inclined dynamic pressure surface) between the sleeve 20 and the bearing portion 11 ′ is in surface contact. Therefore, compared with the case of line contact, the contact surface pressure is remarkably relieved, so that seizure due to twisting at the start of the scroll compressor 100 can be prevented. In addition, the position where the weight 22 is installed is the same position as the point of application of the load acting on the countershaft 6c, so that the centrifugal load generated in the weight 22 along with the radial load Wr acting on the countershaft 6c during operation. Can support force. Here, the point of application of the load acting on the subshaft 6c is the midpoint of the subshaft 6c in the axial direction.

  Further, the circumferential position of the point of application of the load varies depending on the shape and dimensions of the scroll compressor 100. Therefore, the attachment position of the weight 22 on the sleeve 20 may be a central portion with respect to the axial direction, but the circumferential direction is required to be adjusted depending on the type of the scroll compressor 100. For example, alloy tool steel having a hardness of HV1000 or higher may be used as the material of the sleeve 20. Further, as the material of the weight 22, for example, a material having a specific gravity greater than that of iron, such as gold, silver, copper, or platinum, is used. By comprising in this way, the imbalance by centrifugal force is canceled and the stable driving | operation becomes possible. Furthermore, in order to improve the stability at the time of starting, it is desirable to hold the oil level so that the auxiliary bearing 11 is always immersed in the lubricating oil.

  As described above, in the scroll compressor 100 according to Embodiment 1, the auxiliary bearing 11 has the substantially conical bearing portion 11 ′, and the bearing portion 11 ′ supports the substantially conical auxiliary shaft 6c. In the inclined dynamic pressure surface between the countershaft 6c and the bearing portion 11 ′, an opening angle θ1 formed between the pair of buses on the sliding surface of the subshaft 6c is defined as the bearing portion 11. Is set so as to form an angle smaller than the opening angle θ2 formed between the pair of buses on the sliding surface of ′, and a portion of the inclined dynamic pressure surface while the auxiliary shaft 6c is stopped The sleeve 20 provided with the weight 22 is fixed to the auxiliary shaft 6c so that the bearing portion 11 ′ of the auxiliary bearing 11 is in surface contact.

  Therefore, in the scroll compressor 100 according to Embodiment 1, both the radial load Wr and the thrust load Wt can be simultaneously supported in the auxiliary bearing 11. Accordingly, the scroll compressor 100 can ensure long-term reliability and suppress seizure of the auxiliary bearing 11, and can have stable and good startability. In addition, the scroll compressor 100 can reduce costs and improve long-term reliability by using a conical bearing as the auxiliary bearing 11 as compared with a ball bearing.

Embodiment 2. FIG.
FIG. 5 is an enlarged schematic view showing the auxiliary bearing 11a portion of the scroll compressor according to Embodiment 2 of the present invention. Based on FIG. 5, the auxiliary bearing 11a which is the characteristic part of Embodiment 2 is demonstrated in detail. The sub bearing 11a supports the tip end portion (sub shaft 6c) of the main shaft 6 rotatably like the sub bearing 11 described in the first embodiment. In the second embodiment, differences from the first embodiment will be mainly described, and the same parts as those in the first embodiment are denoted by the same reference numerals.

  As shown in FIG. 5, the auxiliary bearing 11 a has a substantially conical bearing portion 11 a ′, and is configured to support the substantially conical auxiliary shaft 6 c ′ with the bearing portion 11 a ′, and In the inclined dynamic pressure surface between the countershaft 6c ′ and the bearing portion 11a ′, an opening angle θ1 formed between the pair of bus bars on the sliding surface of the countershaft 6c ′ is defined as a pair on the sliding surface of the bearing portion 11a ′. Are set so as to form an angle smaller than the opening angle θ2 formed between the buses. Further, a notch 23 is provided at the lower end of the auxiliary bearing 11a in a circumferential shape (so as to surround the bearing portion 11a '). That is, the auxiliary bearing 11a differs from the auxiliary bearing 11 of the first embodiment in that the notch 23 is provided without providing the sleeve.

  By adopting such a structure, during the rotation of the main shaft 6, the inclined sliding surface of the counter shaft 6 c ′ is parallel to the sliding surface of the bearing portion 11 a ′. It can be carried out. Further, when the main shaft 6 is in a rotation stopped state, the main shaft 6 sinks downward and is supported by the notch 23 of the auxiliary bearing 11. At this time, by having the notch 23, the lower end portion of the auxiliary bearing 11 is deformed so as to follow the inclined surface of the auxiliary shaft 6c '. Therefore, the auxiliary shaft 6 c ′ and the bearing portion 11 a ′ of the auxiliary bearing 11 a are in a surface contact state, and it is possible to avoid twisting at the start of the scroll compressor 100. Note that the sleeve 20 may be provided as in the first embodiment.

Embodiment 3 FIG.
FIG. 6 is an enlarged schematic view showing the auxiliary bearing 11b portion of the scroll compressor according to Embodiment 3 of the present invention. Based on FIG. 6, the sub bearing 11b which is the characteristic part of Embodiment 3 is demonstrated in detail. The sub-bearing 11b supports the tip end portion (sub-shaft 6c) of the main shaft 6 in a rotatable manner, similarly to the sub-bearing 11 described in the first embodiment. In the third embodiment, differences from the first and second embodiments will be mainly described, and the same parts as those in the first and second embodiments are denoted by the same reference numerals.

  As shown in FIG. 6, the auxiliary bearing 11b has a bearing portion 11b 'having a substantially conical shape at the upper portion and a curved portion having a curvature radius R at the lower portion, and the upper portion is also substantially conical at the bearing portion 11b'. The lower portion is configured to support the countershaft 6c ″ having a curved surface portion with a radius of curvature R, and the subshaft 6c ′ is arranged on the inclined dynamic pressure surface between the subshaft 6c ″ and the bearing portion 11b ′. The opening angle θ1 formed between the pair of buses on the sliding surface of “′” is made smaller than the opening angle θ2 formed between the pair of buses on the sliding surface of the bearing portion 11b ′. Is set to That is, in the auxiliary bearing 11b, the shapes of the bearing portion 11b ′ and the auxiliary shaft 6c ″ are the same as the bearing portion 11 ′ and the auxiliary shaft 6c of the first embodiment, and the bearing portion 11a ′ and the auxiliary shaft 6c ′ of the second embodiment. Is different.

  With such a structure, during the rotation of the main shaft 6, the inclined sliding surface of the countershaft 6c ″ is parallel to the sliding surface of the bearing portion 11b ′. It can be performed. Further, when the main shaft 6 is in a rotation stopped state, the main shaft 6 sinks downward, and the curved surface portion of the sub shaft 6 c ″ is supported by the curved surface portion of the sub bearing 11 b. Therefore, the auxiliary shaft 6 c ″ and the bearing portion 11 b ′ of the auxiliary bearing 11 b are in a surface contact state, and it is possible to avoid twisting at the start of the scroll compressor 100. Note that a sleeve may be provided as in the first embodiment, or the notch 23 may be formed as in the second embodiment.

  DESCRIPTION OF SYMBOLS 1 Fixed scroll, 2 Swing scroll, 3 Suction port, 4 Discharge port, 5 Compression chamber, 6 Main shaft, 6a Eccentric shaft, 6b Balancer, 6c Sub shaft, 6c 'Sub shaft, 6c' 'Sub shaft, 7 Oil supply mechanism, 7a Oil supply hole, 7b Pump, 8 Housing, 8a Upper housing, 8b Lower housing, 9 Oil return hole, 10 Electric motor, 10a Rotor, 10b Stator, 11 Sub bearing, 11 'Bearing part, 11a Sub bearing, 11a' Bearing part, 11b Sub bearing, 11b 'bearing, 12 Oldham joint, 13 Sealed container, 14 Oil sump, 15 Refrigerant suction pipe, 16 Refrigerant discharge pipe, 17 Swing bearing, 18 Thrust bearing, 19 Main bearing, 20 Sleeve, 21 Pin, 22 weights, 23 notches, 100 scroll compressor, A compression mechanism, B drive mechanism.

Claims (7)

A compression mechanism for compressing the refrigerant;
A drive mechanism for driving the compression mechanism;
A main shaft that transmits the driving force of the drive mechanism to the compression mechanism;
A main bearing provided on one side of the drive mechanism and rotatably supporting the main shaft;
A sub-bearing provided on the other side of the drive mechanism and rotatably supporting the tip of the main shaft;
The secondary bearing is
It has a substantially conical bearing portion, and the bearing portion is configured to support the tip portion of the spindle that is also substantially conical, and in the inclined dynamic pressure surface between the tip portion of the spindle and the bearing portion, The opening angle formed between the pair of bus bars on the sliding surface of the tip end portion of the main shaft is smaller than the opening angle formed between the pair of bus bars on the sliding surface of the bearing section. Set to
The scroll compressor, wherein the bearing portion and the tip end portion of the main shaft are in surface contact with each other when the main shaft is stopped rotating. 2. The scroll compressor according to claim 1, wherein a sleeve provided with a weight in part inside is provided between a tip portion of the main shaft and a sliding surface of the bearing portion. The sleeve is
The scroll compressor according to claim 2, wherein the scroll compressor is fixed to a tip portion of the main shaft at a position shifted by approximately 180 ° from the weight. The sleeve is
The scroll compressor according to claim 2 or 3, wherein the scroll compressor is made of an alloy tool steel having a hardness of HV1000 or more. The weight is
It is comprised with the metal material whose specific gravity is larger than iron. The scroll compressor as described in any one of Claims 2-4 characterized by the above-mentioned. The scroll compressor according to claim 1, wherein a notch is formed so as to surround the bearing portion at a lower end of the auxiliary bearing. The scroll compressor according to claim 1, wherein a curved surface portion is formed at each lower end of the auxiliary bearing and the tip end portion of the main shaft.

Images