JP2013181516A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor achieving miniaturization of a second balancer required for generating moment for unbalance offset, constituting the second balancer of an inexpensive material, and not increasing specifications of a rotor depending on specifications of an orbiting scroll.SOLUTION: A scroll compressor 100 comprises: a second balancer 19 mounted on a lower part of a main shaft 4 and rotated with the main shaft 4; a sub frame 20 provided with a ball bearing 21 rotatably supporting the lower part of the main shaft 4; and a second balancer cover 8 mounted on an upper part of the sub frame 20 and surrounding at least a side surface side of the second balancer 19.

Description

  The present invention relates to a scroll compressor used as one component of a refrigeration cycle employed in, for example, an air conditioner or a refrigeration apparatus.

  Conventional scroll compressors generally include a fixed scroll fixed to a frame, an orbiting scroll having a rotational center that is eccentric with respect to the center of the fixed scroll, and a stator that constitutes an electric mechanism unit. A rotor that constitutes the electric mechanism, a main shaft that is rotationally driven by the electric mechanism, a slider that supports the orbiting scroll to revolve the orbiting scroll, and a main shaft that is eccentric with respect to the main axis. An eccentric shaft portion that is a slider mounting shaft installed on the upper portion of the slider, a compression portion that is mounted on the eccentric shaft portion and includes a fixed scroll, a swing scroll, and the like, and a sealed shell that houses the compression portion and the electric mechanism portion A suction pipe for introducing refrigerant gas into the scroll compressor from the outside, and for discharging refrigerant gas compressed by the scroll compressor to the outside A discharge pipe, a swing scroll and a main shaft are supported, a frame fixed to the shell with bolts or the like with respect to the fixed scroll, a sub-frame that rotatably supports the main shaft below the compression mechanism, and a bottom of the shell. And a positive displacement oil pump that sucks up the oil through the oil supply passage in the main shaft to the slider.

  Also, in the scroll compressor, a first balancer is attached to the upper part of the main shaft and a second balancer is attached to the lower surface of the rotor integrally with the rotor in order to cancel unbalance due to the eccentricity of the orbiting scroll. (For example, refer to Patent Document 1).

  Some of such scroll compressors have a second balancer cover attached in order to reduce loss due to stirring of oil and refrigerant because the second balancer has a substantially semicircular shape. In the scroll compressor to which the second balancer cover is attached, the outer shape of the rotor, the second balancer, and the second balancer cover are formed into a substantially cylindrical shape in a state where the rotor, the second balancer cover and the second balancer cover are assembled together, and the scroll compressor rotates together with the main shaft. It has become.

JP-A-4-124485 (FIG. 1 etc.)

  In the conventional scroll compressor as described in Patent Document 1, if the material and shape of the orbiting scroll differ depending on the type of the scroll compressor, a first balancer and a second balancer corresponding to each model are required. Become. Therefore, a second balancer having a different shape is required for each type of scroll compressor, and the specifications of the second balancer cover increase in order to completely cover the second balancer with the second balancer cover. It is also because the side of the second balancer that is completely covered has a larger effect in order to reduce the loss when the second balancer rotates in the refrigerant atmosphere in which oil exists. Therefore, the rotor specification increases due to the increase in the second balancer specification. As a result, there has been a problem that the sharing of the rotor has not progressed, the work process, labor and cost required for the work have increased, and the production efficiency has been reduced.

  Moreover, in the conventional scroll compressor as described in Patent Document 1, since the second balancer is attached so as to be integrated with the rotor, the distance from the orbiting scroll to the second balancer is short (rotor In order to generate a moment for canceling the unbalance, the second balancer had to be made larger or heavier. For this reason, there is a problem that the second balancer cannot be reduced in size and the scroll compressor cannot be reduced in size and weight. In addition, in order to reduce the size of the second balancer, a material having a large specific gravity must be used, and the second balancer has become expensive.

  Furthermore, the second balancer and the second balancer cover are attached to the rotor by caulking with a rivet, and the centrifugal force of the second balancer exerts a shearing force on the rivet. Therefore, when selecting a rivet, it is necessary to select a rivet that has sufficient strength, and the number of rivets increases depending on the model, resulting in an increase in the cost required for rivets. was there.

  Furthermore, since the rotor and the second balancer are integrated, the second balancer is made of a magnetic material such as iron that can be easily magnetized. The magnetic flux at the time of magnetization leaks to the second balancer, which is a magnetic material, and the efficiency of magnetization is reduced. Further, during operation, the magnetic flux of the magnet in the rotor leaks to the second balancer, and the magnetic force of the rotor that contributes to the torque that moves the scroll compressor is reduced. From these things, problems, such as the performance of a compressor falling, arise. Therefore, the second balancer needs to be made of a non-magnetic material such as brass, and there is a problem that the second balancer is expensive accordingly.

  The present invention has been made to solve at least one of the problems as described above, and does not increase the rotor specifications even by the specifications of the orbiting scroll, and generates a moment for canceling the unbalance. It is an object of the present invention to provide a scroll compressor that realizes a reduction in the size of the second balancer necessary for the second balancer, that is made of an inexpensive material, and that does not increase the rotor specifications even with the swing scroll specifications.

  The scroll compressor according to the present invention is inserted in a container, a stator fixedly supported in the container, a rotor rotatably disposed on the inner peripheral surface side of the stator, and a center portion of the rotor, A main shaft that rotates together with the rotor, a first balancer that is attached to the upper portion of the main shaft and rotates together with the main shaft, a second balancer that is attached to the lower portion of the main shaft and rotates together with the main shaft, and a lower portion of the main shaft. A subframe having a ball bearing that is rotatably supported, and a second balancer cover that is attached to an upper portion of the subframe and surrounds at least a side surface of the second balancer.

  According to the scroll compressor of the present invention, since the second balancer cover is attached to the subframe, the specifications of the rotor and the second balancer cover can be maintained even if the specifications of the second balancer are increased due to an increase in the specifications of the orbiting scroll. There is no need to increase it.

  In addition, since the second balancer is attached to the lower part of the main shaft instead of the rotor, a moment for offsetting the imbalance can be generated even if the second balancer is reduced in size and weight.

  Furthermore, since the second balancer is separated from the rotor, magnetic flux does not leak to the second balancer even if the rotor is made of a magnetic material, and the magnetic force of the rotor does not decrease. An inexpensive magnetic material can be used.

It is a longitudinal cross-sectional view which shows the cross-sectional structural example of the scroll compressor which concerns on Embodiment 1 of this invention. It is a cross-sectional view which shows the cross-sectional structural example of the 2nd balancer part of the scroll compressor which concerns on Embodiment 1 of this invention. It is a longitudinal cross-sectional view which expands and shows the bearing part of the sub-frame of the scroll compressor which concerns on Embodiment 1 of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1.
FIG. 1 is a longitudinal sectional view showing a cross-sectional configuration example 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 one of the components of a refrigeration cycle used in various industrial machines such as a refrigerator, a freezer, a vending machine, an air conditioner, a refrigeration 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. The scroll compressor 100 includes a compression unit including a fixed scroll 9 and a swing scroll 10 and a drive unit including an electric rotary machine 7 and the like. These compression unit and drive unit are accommodated in the container 1. As shown in FIG. 1, in the container 1, the compression part is arrange | positioned at the upper side, and the drive part is arrange | positioned at the lower side, respectively.

  The container 1 is a sealed container in which an upper container 1c and a lower container 1b are provided on the upper and lower parts of the intermediate container 1a. The lower container 1b is an oil sump 23 for storing lubricating oil. A suction pipe 24 for sucking refrigerant gas is connected to the intermediate container 1a. A discharge pipe 25 for discharging refrigerant gas is connected to the upper container 1c.

  The compression unit includes an orbiting scroll 10, a fixed scroll 9, a frame 11, and the like. As shown in FIG. 1, the orbiting scroll 10 is arranged on the lower side, and the fixed scroll 9 is arranged on the upper side. In addition, a thrust plate 14 that supports the swing scroll 10 is provided between the swing scroll 10 and the frame 11. The rocking scroll 10 and the thrust plate 14 are in close contact with each other via a lubricating oil, thereby constituting a thrust bearing.

  The fixed scroll 9 is formed with a wrap portion 9a which is a spiral protrusion standing on one surface. Further, the oscillating scroll 10 is also provided with a wrap portion 10a that is a spiral protrusion that is erected on one surface and has substantially the same shape as the wrap portion 9a. The swing scroll 10 and the fixed scroll 9 are mounted in the container 1 by combining the wrap portion 10a and the wrap portion 9a. In the state where the swing scroll 10 and the fixed scroll 9 are combined, the winding directions of the wrap portion 9a and the wrap portion 10a are opposite to each other.

  And between the lap | wrap part 10a and the lap | wrap part 9a, the compression chamber 26 from which a volume changes relatively is formed. In the fixed scroll 9 and the swing scroll 10, a seal 27 is provided on the wrap portion 9 a and the front end surfaces (upper end surface and lower end surface) of the wrap portion 10 a in order to reduce refrigerant leakage from the front end surfaces of the wrap portion 9 a and wrap portion 10 a. , 28 are arranged.

  The fixed scroll 9 is fixed to the frame 11 with a bolt or the like (not shown). A discharge port 9b is formed at the center of the fixed scroll 9 to discharge the compressed refrigerant gas having a high pressure. Then, the compressed and high pressure refrigerant gas is discharged into the discharge space 33 provided in the upper part of the fixed scroll 9. The refrigerant gas discharged to the discharge space 33 is discharged to the refrigeration cycle via the discharge pipe 25. The discharge port 9b is provided with a discharge valve 29 that prevents the refrigerant from flowing backward from the discharge space 33 to the discharge port 9b.

  The orbiting scroll 10 performs a revolving orbiting motion (oscillating motion) without rotating about the fixed scroll 9 by an Oldham ring 15 for preventing the rotating motion. A hollow cylindrical rocking bearing 13 is formed at a substantially central portion of a surface (hereinafter referred to as a thrust surface) opposite to the surface on which the wrap portion 10a of the rocking scroll 10 is formed. A slider 16 is rotatably inserted into the oscillating bearing 13, and an eccentric shaft portion 4 a provided at the upper end of the main shaft 4 is inserted into a slide surface (center side surface) of the slider 16. And the inner peripheral part of the rocking | fluctuating bearing 13 and the outer peripheral part of the slider 16 closely_contact | adhere via lubricating oil, and comprise a rocking | fluctuating bearing part.

  The drive unit includes a rotor 3 fixed to the main shaft 4, a stator 2, a main shaft 4 that is a rotating shaft, and the like. The rotor 3 is fixed to the main shaft 4 and is rotationally driven when the energization of the stator 2 is started to rotate the main shaft 4. That is, the electric rotating machine 7 is constituted by the stator 2 and the rotor 3.

  The main shaft 4 rotates with the rotation of the rotor 3 to turn the orbiting scroll 10. The upper portion of the main shaft 4 (in the vicinity of the eccentric shaft portion 4a) is supported by a main bearing 12 provided on the frame 11. A sleeve 17 is provided between the main bearing 12 and the main shaft 4 to smoothly rotate the main shaft 4.

  On the other hand, the lower portion of the main shaft 4 is rotatably supported by a ball bearing 21. The ball bearing 21 is press-fitted and fixed in a bearing housing portion 20 a formed at the center portion of the subframe 20 provided at the lower portion of the container 1. Further, the subframe 20 is provided with a positive displacement oil pump 22. A pump shaft 4 b that transmits rotational force to the oil pump 22 is formed integrally with the main shaft 4. Lubricating oil sucked by the oil pump 22 is sent to each sliding portion through an oil hole 4 c formed inside the main shaft 4.

  Here, the oil supply path to the ball bearing 21 will be described. The oil sucked up by the oil pump 22 is sent between the main shaft 4 and the ball bearing 21 through the oil supply hole 4d shown in FIG. A part of the oil lubricated between the main shaft 4 and the ball bearing 21 is discharged from the notch 4e by the centrifugal force due to the rotational movement of the main shaft 4 and sent to the upper portion of the ball bearing 21 to lubricate the ball bearing 21. It has become. 3 is an enlarged longitudinal sectional view showing a bearing portion of the subframe 20 of the scroll compressor 100. As shown in FIG.

  The oil supply hole 4d is formed in the upper part of the inner peripheral surface of the ball bearing 21 of the main shaft 4 so that the oil hole 4c of the main shaft 4 and the outer periphery of the main shaft 4 communicate with each other. Further, the notch 4e is supplied from the oil supply hole 4d and discharges a part of the oil lubricated between the main shaft 4 and the ball bearing 21 to the outside of the outer periphery of the main shaft 4 by centrifugal force due to the rotational motion of the main shaft 4. It is. The oil supply hole 4d and the notch 4e allow oil supply to the ball bearing 21 from the upper part of the ball bearing 21.

  In addition, a first balancer 18 and a second balancer 19 are provided above and below the main shaft 4 in order to cancel out the imbalance with respect to the center of rotation of the orbiting scroll 10 and the main shaft 4. The first balancer 18 is fixed to the upper portion of the main shaft 4 by shrink fitting, and the second balancer 19 is also fixed to the lower portion of the main shaft 4 by shrink fitting.

  A cylindrical second balancer cover 8 is attached to the upper portion of the subframe 20 and is disposed so as to surround at least the side surface side of the second balancer 19. At this time, since the second balancer cover 19 is attached to the upper portion of the subframe 20, the second balancer cover 8 is disposed so as to surround the side surface of the upper surface of the ball bearing 21 housed in the bearing housing portion 20a. More desirable. The second balancer cover 8 has a lower end attached to the upper portion of the subframe 20 and is formed so as to protrude upward in the axial direction from the lower end toward the upper end. The second balancer 19 is configured to rotate inside the second balancer cover 8. The second balancer cover 8 has a function of suppressing the stirring of the refrigerant and oil by the second balancer 19 and suppressing the scattering of oil supplied to the ball bearing 21 from the notch 4e (see FIG. 3). . Note that the second balancer cover 8 may be open or closed at the top.

  FIG. 2 is a cross-sectional view illustrating a cross-sectional configuration example of the second balancer 19 portion of the scroll compressor 100. The 2nd balancer 19 and the 2nd balancer cover 8 are demonstrated based on FIG. FIG. 2 illustrates an example of the planar shape of the second balancer 19, but the planar shape of the second balancer 19 is not limited to the shape illustrated in FIG. 2.

  As described above, the second balancer 19 is fixed to the lower portion of the main shaft 4. Further, the second balancer cover 8 is disposed so as to surround the side surface side of the second balancer 19. From FIG. 2, it can be seen that the second balancer 19 rotates inside the second balancer cover 8. That is, in the scroll compressor 100, the second balancer 19 and the second balancer cover 8 are separated from the rotor 3 and are installed below the main shaft 4. The second balancer cover 8 is attached to the subframe 20 side, and the main shaft 4 and the second balancer 19 are rotated inside the second balancer cover 8. Since the moment sum for balancing does not change, the bearing load does not change even if the second balancer 19 is installed at a position away from the rotor 3.

  By doing so, the scroll compressor 100 can generate a moment for offsetting the imbalance even if the second balancer 19 is downsized. In addition, since it is no longer necessary to assemble the second balancer 19 integrally with the rotor 3, it is no longer necessary to increase the specifications of the rotor 3 and the second balancer cover 8 even if the specifications of the second balancer 19 increase.

  Further, since the second balancer 19 is fixed to the main shaft 4 and the second balancer cover 8 is fixed to the subframe 20, there is no portion eccentric to the rotor 3. Therefore, there is no radial load applied to the rivet, and the strength of the rivet against shearing can be ignored. That is, it is not necessary to select an expensive rivet, and the cost required for the rivet is not increased.

  Furthermore, the second balancer 19 is installed away from the rotor 3 so that the material of the second balancer 19 can be made of a magnetic material such as iron. For this reason, it is not necessary to use a non-magnetic material such as brass as the material of the second balancer, and even if the second balancer 19 is made of a magnetic material that can be easily magnetized, the magnetic flux during magnetization can be reduced. Leakage into the second balancer 19 reduces the efficiency of magnetization, and during operation, the magnetic flux of the magnet in the rotor leaks into the second balancer 19 and the magnetic force of the rotor 3 contributing to the torque that moves the scroll compressor 100 is reduced. In addition, problems such as deterioration in the performance of the scroll compressor 100 no longer occur. Accordingly, the second balancer 19 can be formed at low cost.

  Furthermore, by disposing the second balancer 19 away from the rotor 3, even if the second balancer 19 is reduced in weight and size, it is possible to generate a moment sufficient to cancel the imbalance.

  Furthermore, the second balancer cover 8 is disposed so as to surround the side surface side of the second balancer 19, and the second balancer cover 8 is attached to the upper portion of the subframe 20, so that the side surface side of the upper surface of the ball bearing 21 is also surrounded. Therefore, oil can be supplied to the ball bearing 21 and the oil scattered by the stirring of the second balancer 19 and the ball bearing 21 can be suppressed from being sucked into the compression portion and the oil circulation amount being increased.

Next, the operation of the scroll compressor 100 will be described.
When a voltage is applied to the electric rotary machine 7, a current flows through the electric wire portion of the stator 2 and a magnetic field is generated. This magnetic field acts to rotate the rotor 3. When the rotor 3 rotates, the main shaft 4 is rotationally driven accordingly. When the main shaft 4 is driven to rotate, the slider 16 also rotates in the rocking bearing 13 via the eccentric shaft portion 4a. The rocking scroll 10 whose rotation is suppressed by the Oldham ring 15 performs rocking motion.

  When the rotor 3 rotates, the second balancer 19 fixed to the lower part of the main shaft 4 and the first balancer 18 fixed to the upper part of the main shaft 4 keep a balance with respect to the eccentric revolving motion of the orbiting scroll 10. ing. As a result, the orbiting scroll 10 that is eccentrically supported on the upper portion of the main shaft 4 is swung to start revolving and compress the refrigerant by a known compression principle.

  As a result, part of the refrigerant gas flows into the compression chamber 26 via the suction port (not shown) of the frame 11 and the suction process is started. Further, the remaining part of the refrigerant gas passes through the notch (not shown) of the steel plate of the stator 2 to cool the electric rotary machine 7 and the lubricating oil.

  The compression chamber 26 moves to the center of the orbiting scroll 10 by the orbiting motion of the orbiting scroll 10, and the volume is further reduced. Through this process, the refrigerant gas sucked into the compression chamber 26 is compressed. At this time, the fixed scroll 9 and the orbiting scroll 10 are subjected to a load to be separated in the axial direction by the compressed refrigerant gas, and this load is supported by the thrust plate 14 (thrust bearing). The compressed refrigerant passes through the discharge port 9 b of the fixed scroll 9, pushes the discharge valve 29 open, and flows into the discharge space 33. Then, the liquid is discharged from the container 1 through the discharge pipe 25.

  During the series of operations as described above, between the swing scroll 10 and the thrust plate 14, between the wrap portion 10a and the wrap portion 9a (compression chamber 26), between the seal 28 of the wrap portion 9a and the swing scroll 10. Between the seal 27 of the wrap portion 10a and the fixed scroll 9, between the Oldham groove and the key portion of the Oldham ring 15, between the rocking bearing 13 and the slider 16, and between the eccentric shaft portion 4a and the slider 16. Lubricating oil is supplied to each sliding portion such as between the surface, between the main bearing 12 and the sleeve 17 and between the sleeve 17 and the main shaft 4. These sliding portions have the same atmosphere as the refrigerant having a relatively low temperature sucked into the container 1. Thereby, these sliding parts are cooled by the comparatively low temperature refrigerant | coolant suck | inhaled in the container 1, and the temperature rise is suppressed.

  Note that the low-pressure refrigerant gas in the container 1 and the high-pressure refrigerant gas in the container 1 are partitioned so as to be kept airtight by the fixed scroll 9 and the frame 11, and therefore do not coexist in the container 1. Moreover, the lubricating oil supplied to each sliding part returns to the oil sump 23 again via an oil return path (not shown) by gravity. When the energization of the stator 4 is stopped, the scroll compressor 100 stops operation.

  1 container, 1a middle container, 1b lower container, 1c upper container, 2 stator, 3 rotor, 4 main shaft, 4a eccentric shaft, 4b pump shaft, 4c oil hole, 4d oil supply hole, 4e notch, 7 electric rotation Machine, 8 Second balancer cover, 9 Fixed scroll, 9a Lapping part, 9b Discharge port, 10 Orbiting scroll, 10a Lapping part, 11 Frame, 12 Main bearing, 13 Oscillating bearing, 14 Thrust plate, 15 Oldham ring, 16 Slider, 17 Sleeve, 18 1st balancer, 19 2nd balancer, 20 Subframe, 20a Bearing housing, 21 Ball bearing, 22 Oil pump, 23 Oil sump, 24 Suction pipe, 25 Discharge pipe, 26 Compression chamber, 27 Seal , 28 Seal, 29 Discharge valve, 33 Discharge space, 100 Compressor.

Claims (3)

A container,
A stator fixedly supported in the container;
A rotor rotatably disposed on the inner peripheral surface side of the stator;
A main shaft inserted into the center of the rotor and driven to rotate together with the rotor;
A first balancer attached to an upper portion of the main shaft and rotating together with the main shaft;
A second balancer attached to a lower portion of the main shaft and rotating together with the main shaft;
A subframe including a ball bearing that rotatably supports a lower portion of the main shaft;
A scroll compressor, comprising: a second balancer cover attached to an upper portion of the subframe and surrounding at least a side surface of the second balancer. The second balancer is
It is comprised with the magnetic body. The scroll compressor of Claim 1 characterized by the above-mentioned. The main shaft is formed with a notch for supplying oil from the upper part of the ball bearing,
The second balancer cover is
The scroll compressor according to claim 1, wherein the scroll compressor surrounds the outer periphery of the ball bearing.

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