JP2011012592A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor reducing noise without dropping compression efficiency.SOLUTION: The compressor 1 includes a sealed casing 10, and a motor 20 held in the sealed casing 10 and including a rotor and a stator 52 arranged at a radial direction outside of the rotor 51. A sound absorption chamber 54a which acts as a Helmholtz resonator having a sound absorption chamber opening on a rotor lower surface 53a which is a lower surface of a rotor body 53 is disposed at the rotor body 53 of the rotor 51. The sound absorption chamber 54a is arranged with 180 interval with respect to a rotary shaft O of the rotor body 53 and is disposed inside of a magnet 60b embedded in the rotor body 53 in a plane view.

Description

  The present invention relates to a compressor provided with a sound absorption chamber for reducing noise generated during operation.

  Conventionally, by providing a Helmholtz-type resonance chamber in a compressor, noise generated during operation of the compressor has been reduced. As an example of such a compressor, in Patent Document 1, a Helmholtz type resonance chamber communicating with the compression chamber is formed, and a communication path between the resonance chamber and the compression chamber is operated according to the operating state of the compressor. A compressor having a silencing structure of a rotary compressor that opens and closes by a valve body is disclosed.

Japanese Utility Model Publication No. 4-100092

  However, in the compressor including the resonance chamber disclosed in Patent Document 1, the refrigerant gas compressed in the compression chamber may remain in the resonance chamber, and if the refrigerant gas is sucked into the compression chamber in this state, the resonance is generated. Since the refrigerant gas remaining in the chamber expands in the compression chamber in a low pressure state, there is a problem that the compression efficiency is lowered.

  Therefore, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a compressor that can reduce the noise of the compressor without reducing the compression efficiency. .

  A compressor according to a first aspect of the present invention includes a hermetic container, and a drive mechanism that is housed in the hermetic container and includes a rotor and a stator that is disposed on the outer side in the radial direction of the rotor. A sound-absorbing chamber serving as a Helmholtz resonator is provided.

  In this compressor, since the sound absorption chamber, which is a Helmholtz resonator, does not communicate with the compression chamber, and compressed gas does not remain in the sound absorption chamber, it is possible to reduce noise without reducing the compression efficiency. Become. Further, when this sound absorbing chamber is provided on the upper surface of the rotor, there is a possibility that the lubricating oil circulating in the compressor flows into the sound absorbing chamber. In this compressor, the sound absorbing chamber is provided on the lower surface of the rotor. Therefore, the noise can be reduced without the lubricating oil flowing into the sound absorption chamber.

  A compressor according to a second aspect of the present invention is the compressor according to the first aspect, wherein the rotor has a magnet extending along the axial direction, and the sound absorption chamber is disposed inside the magnet in a plan view. Has been.

  In this compressor, since the sound absorbing chamber is disposed inside the magnet, the sound absorbing chamber does not hinder the flow of magnetic flux passing through the iron plates of the rotor and the stator, thereby reducing the efficiency of the motor. Therefore, noise can be reduced.

  A compressor according to a third invention is the compressor according to the first or second invention, wherein a plurality of sound absorbing chambers are provided on the lower surface of the rotor, and the plurality of sound absorbing chambers are in plan view. They are arranged at substantially equal angular intervals around the rotation axis of the rotor.

  In this compressor, a plurality of sound absorbing chambers are arranged at substantially equal angular intervals around the rotation axis of the rotor in plan view, so that when the rotor rotates, the sound absorbing chambers alternately serve as a muffler of the compression mechanism. It periodically opposes the provided outlet. Then, since the plurality of sound absorbing chambers periodically absorb the noise caused by the refrigerant gas discharged from the discharge port, the sound absorption timing is not biased, and the noise can be reduced stably.

  A compressor according to a fourth aspect of the present invention is the compressor according to any one of the first to third aspects, wherein the drive mechanism includes a crankshaft penetrating the center of the rotor, and an eccentricity provided on the crankshaft. The sound absorbing chamber is arranged symmetrically with respect to a first straight line passing through the center of the crankshaft and the center of the eccentric portion in plan view.

  In this compressor, since the weight balance of the two parts partitioned by the first straight line in the rotor is maintained in a plan view, it is possible to reduce the vibration of the rotor during the operation of the drive mechanism.

  A compressor according to a fifth invention is the compressor according to any one of the first to fourth inventions, wherein the drive mechanism includes a crankshaft penetrating the center of the rotor, and an eccentric portion provided on the crankshaft. And the sound absorption chamber is perpendicular to the first straight line passing through the center of the crankshaft and the center of the eccentric portion in plan view and symmetrical with respect to the second straight line passing through the center of the crankshaft. Is arranged.

  In this compressor, since the weight balance of the two parts partitioned by the second straight line perpendicular to the first straight line in the rotor in a plan view is maintained, it is possible to reduce the vibration of the rotor during operation of the drive mechanism. It becomes.

  As described above, according to the present invention, the following effects can be obtained.

  In the first invention, as described above, the sound absorption chamber, which is a Helmholtz resonator, does not communicate with the compression chamber, and the compressed gas does not remain in the sound absorption chamber, so that noise is reduced without lowering the compression efficiency. It becomes possible to do. Further, when this sound absorbing chamber is provided on the upper surface of the rotor, there is a possibility that the lubricating oil circulating in the compressor flows into the sound absorbing chamber. In this compressor, the sound absorbing chamber is provided on the lower surface of the rotor. Therefore, the noise can be reduced without the lubricating oil flowing into the sound absorption chamber.

  In the second invention, as described above, since the sound absorbing chamber is disposed inside the magnet, the sound absorbing chamber does not hinder the flow of magnetic flux passing through the iron plates of the rotor and the stator. Noise can be reduced without reducing efficiency.

  In the third invention, as described above, the plurality of sound absorbing chambers are arranged at substantially equal angular intervals around the rotation axis of the rotor in plan view, so that the sound absorbing chambers are alternately arranged when the rotor rotates. It periodically opposes the discharge port provided in the muffler of the compression mechanism. Then, since the plurality of sound absorbing chambers periodically absorb the noise caused by the refrigerant gas discharged from the discharge port, the sound absorption timing is not biased, and the noise can be reduced stably.

  In the fourth aspect of the invention, as described above, the weight balance between the two portions partitioned by the first straight line in the rotor is maintained in plan view, so that it is possible to reduce the vibration of the rotor during operation of the drive mechanism. .

  In the fifth invention, as described above, since the weight balance between the two parts partitioned by the second straight line perpendicular to the first straight line in the plan view is maintained in plan view, the vibration of the rotor during operation of the drive mechanism is reduced. It becomes possible to reduce.

It is sectional drawing of the compressor which concerns on 1st Embodiment. It is a figure which shows the rotor which concerns on 1st Embodiment, (A) is AA 'longitudinal cross-sectional view in (B), (B) is a bottom view of the rotor seen from the arrow direction of (A). is there. It is a figure which shows the rotor, shaft, and balance weight which concern on 1st Embodiment, (A) is a X-X 'cross section in (B), (B) is a top view. It is a figure which shows the rotor, shaft, and balance weight which concern on 2nd Embodiment, (A) is a X-X 'cross section in (B), (B) is a top view. It is a figure which shows an example of a rotor, a shaft, and a balance weight, (A) is a X-X 'cross section in (B), (B) is a top view. It is a figure which shows the 1st example of a rotor. It is a figure which shows the 2nd example of a rotor. It is a figure which shows the 3rd example of a rotor. It is a figure which shows the 4th example of a rotor.

  Hereinafter, an embodiment of a compressor according to the present invention will be described based on the drawings.

(First embodiment)
FIG. 1 is a longitudinal sectional view of a compressor according to a first embodiment of the present invention. 2A and 2B are views showing the rotor, in which FIG. 2A is a longitudinal sectional view of the rotor, and FIG. 2B is a bottom view of the rotor. Note that FIG. 2A is a cross-sectional view taken along line A-O-B in FIG. 3A and 3B are diagrams showing a shaft integrally formed with the rotor body, in which FIG. 3A is a longitudinal sectional view of the shaft, and FIG. 3B is a top view of the shaft. Hereinafter, based on FIGS. 1-3, the compressor which concerns on embodiment of this invention is demonstrated. In addition, the cross section of the rotor shown in FIG. 1 is an AA ′ cross section of FIG.

[Overall configuration of compressor]
As shown in FIG. 1, the compressor 1 is configured as a one-cylinder type rotary compressor for refrigerant, and compresses refrigerant introduced from an accumulator 2 that communicates with a compression mechanism 30 (described later) through a suction pipe 3. And the compressed refrigerant compressed from the discharge pipe 11a arrange | positioned at the upper end part is discharged | emitted. The compressor 1 includes a hermetic casing 10, a motor 20 as a drive mechanism disposed in the hermetic casing 10, and a compression mechanism 30 driven by the motor 20. The compressor 1 is a so-called high-pressure dome type compressor, and a compression mechanism 30 is disposed below the motor 20 in the sealed casing 10. In addition, lubricating oil 40 supplied to each sliding portion of the compression mechanism 30 is stored in the lower portion of the hermetic casing 10.

[Structure of sealed casing]
The sealed casing 10 includes a top 11, a pipe 12, and a bottom 13 for forming a sealed space. The top 11 is provided as a member that closes the opening at the upper end of the pipe 12. The top 11 is provided with a discharge pipe 11 a for discharging the high-temperature and high-pressure refrigerant compressed by the compression mechanism 30 to the outside of the sealed casing 10. The top 11 is provided with a terminal terminal 11b connected to the motor 20 which is a driving mechanism. The bottom 13 is provided as a member that closes the opening at the lower end of the pipe 12, and an oil reservoir 41 is provided therein.

[Motor configuration]
The motor 20 includes a shaft 50, a rotor 51 (rotor) to which the shaft 50 is attached, and a stator 52 disposed on the radially outer side of the rotor 51 via an air gap. The rotor 51 includes a rotor main body 53 made of laminated electromagnetic steel plates and four magnets 60 a to 60 d embedded in the rotor main body 53. The rotor body 53 is formed with Helmholtz type sound absorbing chambers 54a and 54b, which will be described later. Furthermore, balance weights 61a and 61b are provided on the upper and lower end faces of the rotor body 53 to prevent the rotor body 53 from being tilted during rotation by stabilizing the center of gravity.

  The stator 52 is fixed to the pipe 12 by shrink fitting. A notch is provided between the pipe 52 and the outer periphery of the stator 52 to form a through hole. The refrigerant gas discharged from the compression mechanism 30 moves from the lower side to the upper side through the through hole. The stator 52 includes a core 55, an upper insulator 56 and a lower insulator 57, which are disposed on both upper and lower end surfaces of the core 55, and a coil. The core 55 is made of, for example, a plurality of stacked steel plates. The upper insulator 56 and the lower insulator 57 are made of a resin material having high heat resistance such as liquid crystal polymer (LCP), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), polyimide, and polyester. In addition, in order to improve the intensity | strength, the upper insulator 56 and the lower insulator 57 may be comprised with the material containing glass fiber, for example.

  The motor 20 rotates the rotor 51 together with the shaft 50 by applying an electromagnetic force generated by the stator 52 to the magnets 60 a to 60 d embedded in the rotor 51. The shaft 50 has a crankshaft 50a that passes through a shaft hole 58 formed in a substantially central portion of the rotor main body 53, and an eccentric portion 50b provided at the lower end portion of the crankshaft 50a. A roller 34 is attached to the eccentric portion 50b. The crankshaft 50a rotates together with the rotor 51 to rotate the eccentric portion 50b in the cylinder chamber A1, and compresses the refrigerant gas flowing into the cylinder chamber A1.

[Configuration of compression mechanism]
The compression mechanism 30 includes a front muffler 31, a front head 32, a cylinder 33, and a rear head 35 that are disposed from above to below along the rotation axis O of the rotor 51. The front muffler 31 reduces noise caused by pulsation of refrigerant discharged from a discharge port (not shown) provided in the front head 32. A discharge port 36 is formed at a position close to the front head 32 on the upper surface of the front muffler 31, and the discharge port 36 discharges the refrigerant whose noise is reduced by the front muffler 31 to the primary space B1. The discharge port 36 faces a lower end surface (hereinafter referred to as “rotor lower surface 53a”) of a rotor main body 53 described later. Further, since the sound absorbing chambers 54a and 54b described later have openings in the rotor lower surface 53a, the discharge port 36 also faces the sound absorbing chambers 54a and 54b.

  The front head 32 is joined to the upper surface of the cylinder 33 and closes the opening at the upper end of the cylinder chamber A1. The front head 32 is provided with a discharge port (not shown) for discharging the refrigerant compressed in the cylinder chamber A1 to the muffler space C1 formed by the front muffler 31.

  The cylinder 33 is provided with a cylinder chamber A1 at the center thereof. In the cylinder chamber A1, an eccentric portion 50b that is eccentrically rotated along with the rotation of the crankshaft 50a is disposed. The cylinder chamber A1 communicates with the muffler space C1 via a discharge port (not shown) provided in the front head 32 described above. Therefore, the refrigerant compressed by the eccentric rotational movement of the roller 34 attached to the eccentric portion 50b is guided from the cylinder chamber A1 to the muffler space C1. The roller 34 performs eccentric rotational movement along the inner peripheral surface of the cylinder chamber A1, and compresses the refrigerant sucked from the accumulator 2. Blades (not shown) are arranged on the outer peripheral surface of the roller 34, and each of the rollers 34 and the blade is configured as a separate body.

[Configuration of rotor]
Next, the rotor main body 53 constituting the rotor 51 will be described. As shown in FIG. 2B, the rotor main body 53 has two sound absorbing chambers 54a and 54b, which are Helmholtz type sound absorbing chambers, and a shaft hole 58 for allowing the crankshaft 50a to pass therethrough. . In addition, four magnets 60 a to 60 d for rotating around the rotation axis O are embedded in the rotor body 53.

  The shaft hole 58 is for penetrating and fitting the crankshaft 50a, and is provided at a substantially central portion of the rotor body 53 in a plan view. The shaft hole 58 has a cylindrical shape having a diameter substantially the same as the diameter of the crankshaft 50 a, and the central axis thereof coincides with the rotation axis O of the rotor 51 (that is, the rotation axis of the rotor main body 53).

  Magnet 60a-60d is a plate-shaped magnet. The rotor body 53 is provided with attachment holes having substantially the same shape as the magnets 60a to 60d. The magnets 60a to 60d are attached to the attachment holes and embedded in the rotor body 53. Further, as shown in FIG. 2B, the magnets 60a to 60d are magnets 60a, 60b, 60.degree. At intervals of about 90.degree. Clockwise about the rotation axis O when viewed from the lower surface (rotor lower surface) 53a of the rotor body 53. 60c and 60d are arranged in this order. From these magnets 60 a to 60 d, magnetic flux flows along the dotted line schematically shown in FIG. 2B outside the rotor body 53 in the radial direction, and magnetism generated from the coil wound around the core 55. The rotor body 53 is rotated by interacting with the force.

[Configuration of sound absorption chamber]
The sound absorption chambers 54a and 54b are Helmholtz resonators and are provided on the rotor lower surface 53a. The openings (sound absorption chamber openings) 541a and 541b are provided on the rotor lower surface 53a. As shown in FIG. 1, the rotor lower surface 53 a faces a primary space B <b> 1 that is a space between the motor 20 and the compression mechanism 30, and faces a discharge port 36 described later provided in the compression mechanism 30. . Therefore, the sound absorption chamber openings 541a and 541b provided on the rotor lower surface 53a are also opposed to the discharge port 36. Both of the sound absorbing chambers 54a and 54b have the same structure and function. Therefore, the structure and function of the sound absorbing chamber 54a will be described as an example.

  As shown in FIG. 2A, the sound absorbing chamber 54a includes a sound absorbing chamber opening 541a, an inlet portion 542a, and a resonance chamber 543a connected to the inlet portion 542a. The inlet portion 542a and the resonance chamber 543a are both cylindrical, and the diameter of the resonance chamber 543a is larger than the diameter of the inlet portion 542a. Further, the upper end portion of the inlet portion 542a and the lower end portion of the resonance chamber 543a are connected, and one space is formed by the inlet portion 542a and the resonance chamber 543a. By providing such a structure, when pressure pulsation occurs in the gas discharged from the discharge port 36 of the compression mechanism 30 and noise is generated, the sound wave passes through the gas filling the inlet portion 542a and the resonance chamber 543a. It penetrates into and resonates with the inlet 542a and the resonance chamber 543a. As a result, the sound energy of the noise of the discharged gas is converted into heat energy, the sound energy is reduced, and the noise is reduced.

  As shown in FIG. 2B, the sound absorbing chambers 54a and 54b are arranged at intervals of 180 ° about the rotation axis O of the rotor main body 53 in plan view. With this arrangement, when the rotor body 53 rotates about the rotation axis O, the sound absorbing chambers 54a and 54b alternately and periodically face the discharge ports 36 of the compression mechanism 30. Then, since the sound absorption chambers 54a and 54b periodically absorb noise caused by the pulsation of the refrigerant gas discharged from the discharge holes 36, the sound absorption timing is not biased. The sound absorbing chambers 54a and 54b are disposed on the inner side of the four magnets 60a to 60d on the rotor lower surface 53a. That is, the sound absorption chambers 54a and 54b are disposed outside the range in which the magnetic flux generated from the magnets 60a to 60d flows.

[Configuration of balance weight]
Next, the balance weight will be described with reference to FIG. FIG. 3 is a view showing the shaft 50 configured integrally with the rotor main body 53, and FIG. 3A is a cross-sectional view of the first straight line XX ′ cross section of FIG. FIG. 3B is a top view seen from the direction of the arrow in FIG. Note that the first straight line XX ′ in FIG. 3B is a straight line connecting the rotation axis O and the center C of the eccentric portion 50b, and the second straight line YY ′ is the first straight line XX ′. A straight line that passes through the rotation axis O is vertical.

  The balance weights 61a and 61b are disposed on the upper end surface and the lower end surface of the rotor main body 53, respectively, and are made of the same material, and the shape thereof is a semi-ring shape as shown in FIG. However, the thickness of the balance weight 61a disposed on the lower end surface is thicker than the thickness of the balance weight 61b disposed on the upper end surface, as shown in FIG. Accordingly, the balance weight 61a is heavier than the balance weight 61b.

  Next, the positions where the balance weights 61a and 61b are disposed will be described. For convenience of explanation, in FIG. 3B, the center C side of the eccentric portion 50b is “right” with respect to the second straight line YY ′, and the opposite side of the center C is with respect to the second straight line YY ′. The “left side”, the Y side from the first straight line XX ′ is referred to as “upper side”, and the Y ′ side from the first straight line XX ′ is referred to as “lower side”.

  When the sound absorbing chamber is not formed in the rotor body 53, the right side portion of the eccentric part 50b is larger than the left side part, so that the center of gravity of the shaft 50 configured integrally with the rotor body 53 is biased to the right side in the left-right direction. ing. On the other hand, since the shaft 50 and the rotor body 53 are both symmetrical with respect to the first straight line XX ′, the center of gravity of the shaft 50 configured integrally with the rotor body 53 is not biased in the vertical direction, and the rotation axis O Is consistent with

  Therefore, in order to eliminate the deviation of the center of gravity in the left-right direction, that is, to eliminate the difference between the weight of the right side portion and the weight of the left side portion, the heavy balance weight 61a is disposed on the left side of the rotor lower surface 53a. The small balance weight 61 b is disposed on the right side of the upper surface of the rotor body 53. On the other hand, the balance weights 61a and 61b are arranged so as to be line-symmetric with respect to the first straight line X-X 'in order to prevent the deviation of the center of gravity in the vertical direction. Accordingly, as shown in FIG. 3B, the balance weights 61a and 61b are arranged at an interval of 180 ° in a plan view, and the positional relationship with respect to the second straight line YY ′ in the plan view. They are line-symmetric or point-symmetric with respect to the rotation axis O.

[Arrangement of sound absorption chamber]
The sound absorbing chambers 54a and 54b are provided so that the center of gravity of the shaft 50 configured integrally with the rotor body 53 is not biased in the vertical direction and the horizontal direction. Therefore, it is necessary to provide the sound absorption chambers 54a and 54b so as to be line symmetric with respect to the first straight line XX ′ and the second straight line YY ′. First, in order to prevent the center of gravity from being biased in the left-right direction, the sound absorption chambers 54a and 54b are arranged symmetrically with respect to the second straight line YY ′ (see FIG. 3A). That is, the sound absorbing chambers 54a and 54b are arranged at intervals of 180 ° with respect to the central axis O. That is, the sound absorbing chambers 54a and 54b are arranged so as to be point-symmetric with respect to the central axis O (see FIG. 3B).

  Furthermore, in order to prevent the center of gravity from being biased in the vertical direction, the sound absorption chambers 54a and 54b are arranged symmetrically with respect to the first straight line X-X '. That is, the circular cross sections of the sound absorbing chambers 54a and 54b are symmetrical with respect to the first straight line XX ′, that is, the centers of the inlet portions 541a and 541b and the resonance chambers 542a and 542b are the first straight line XX ′. It arrange | positions so that it may become the top (refer FIG. 3 (B)).

  As described above, the sound absorbing chambers 54a and 54b are arranged in a line symmetry with respect to the first straight line XX ′ and the second straight line YY ′ in plan view, so that the shaft 50 configured integrally with the rotor body 53 can be obtained. Noise caused by pulsation of refrigerant gas discharged from the discharge port 36 of the compression mechanism 30 while preventing the center of gravity from being biased in the vertical direction and the left-right direction (that is, while the center of gravity is viewed in plan and coincides with the rotation axis O). Can be reduced.

(Characteristics of the compressor according to the first embodiment)
The compressor according to the first embodiment has the following characteristics.

  In the compressor according to the first embodiment, the sound absorption chambers 54a and 54b are not in communication with the compression chamber B1, and the compressed refrigerant gas does not remain in the sound absorption chambers 54a and 54b, thereby reducing the compression efficiency. Noise can be reduced without any problems. Further, when a sound absorbing chamber is provided on the upper surface of the rotor body 53, there is a possibility that the lubricating oil circulating in the compressor flows into the sound absorbing chamber. On the other hand, in the compressor of the first embodiment, since the sound absorbing chambers 54a and 54b are provided so as to have the sound absorbing chamber openings 541a and 541b on the lower surface of the rotor lower surface 53a, the lubricating oil 40 is supplied to the sound absorbing chambers 54a and 54a. Noise can be reduced without flowing into 54b.

  Further, in the compressor of the present embodiment, the sound absorbing chambers 54 a and 54 b are disposed inside the magnets 60 a to 60 d provided in the rotor main body 53, and the sound absorbing chambers 54 a and 54 b are the iron plates of the rotor 51 and the stator 52. Since the flow of the magnetic flux passing through the inside is not hindered, the noise can be reduced without reducing the efficiency of the motor 20.

  Further, in the compressor of the present embodiment, the sound absorbing chambers 54a and 54b are arranged at an interval of 180 ° with the rotation axis O as the center, so that when the rotor main body 53 rotates, the sound absorbing chambers 54a and 54b are alternately arranged. It periodically faces the discharge port 36 of the compression mechanism 30. Accordingly, there is no bias in the sound absorption timing, and noise can be stably reduced.

  Further, in the compressor of the present embodiment, the sound absorbing chambers 54a and 54b are arranged symmetrically with respect to the first straight line XX ′ and the second straight line YY ′, and thus are configured integrally with the rotor body 53. While preventing the center of gravity of the shaft 50 from deviating vertically and horizontally (that is, making the center of gravity coincide with the rotation axis O), noise caused by the pulsation of the refrigerant gas discharged from the discharge port 36 of the compression mechanism 30 is generated. It becomes possible to reduce.

(Second Embodiment)
In the first embodiment, the case where two sound absorbing chambers are provided in the rotor body has been described, but the number of sound absorbing chambers is not limited thereto. Therefore, in the second embodiment, a case where one sound absorbing chamber is provided in the rotor body will be described with reference to FIGS.

  FIG. 4 is a view showing the shaft 50 configured integrally with the rotor body 530, and FIG. 4A is a cross-sectional view of the first straight line XX ′ cross section of FIG. FIG. 4B is a top view seen from the direction of the arrow in FIG. The description of the first straight line X-X ′ and the second straight line Y-Y ′ in FIG. 4B is the same as the description in FIG. 3 of the first embodiment.

  Since the shaft 50 and the eccentric portion 50b are the same as those according to the first embodiment, the description thereof is omitted. On the other hand, the rotor body 530 is different from the rotor body 53 according to the first embodiment, and the sound absorbing chamber formed inside is only the sound absorbing chamber 54b. The arrangement of the sound absorption chamber 54b will be described later. The structure and function of the sound absorption chamber 54b are the same as those in the first embodiment.

  The balance weights 62a and 62b are disposed on the lower end surface and the upper end surface of the rotor body 530, respectively. The balance weights 62a and 62b are made of the same material, and are both disk-shaped as shown in FIGS. Hereinafter, the arrangement of the balance weights 62a and 62b will be described.

  First, for convenience of explanation, a case where the sound absorbing chamber 54b is not formed in the rotor body 530 will be described. FIG. 5 is a view showing the shaft 50 configured integrally with the rotor body 530 ′ in which no sound absorbing chamber is formed. FIG. 5A is a longitudinal sectional view of the shaft 50, and FIG. ) Is a top view of the shaft 50.

  The center of gravity of the shaft 50 configured integrally with the rotor body 530 'is biased to the right in the left-right direction because the right portion of the eccentric portion 50b is larger than the left portion. On the other hand, since the shaft 50 and the rotor body 530 'are both symmetrical with respect to the first straight line X-X', the center of gravity is not biased in the vertical direction and coincides with the rotation axis O.

  Accordingly, in order to eliminate the deviation of the center of gravity in the left-right direction, the balance weight 62a ′ having a large weight is disposed on the left side of the rotor lower surface 530a, and the balance weight 62b ′ having a small weight is disposed on the right side of the upper surface of the rotor body 530. ing. On the other hand, the balance weights 62a 'and 62b' are arranged so as to be symmetric with respect to the first straight line X-X 'in order to prevent the deviation of the center of gravity in the vertical direction.

  On the other hand, in the shaft 50 configured integrally with the rotor main body 530 in which the sound absorbing chamber 54b is formed, the left side portion of the rotor main body 530 is heavier than the right side portion in which the sound absorbing chamber 54b is formed. As for the shaft 50, since the right side portion of the eccentric portion 50b is larger than the left side portion, the right side portion is heavier than the left side portion. On the other hand, since the shaft 50 and the rotor body 530 'are both symmetrical with respect to the first straight line X-X', the center of gravity is not biased in the vertical direction and coincides with the rotation axis O.

  Accordingly, the balance weights 62a and 62b are disposed so that the difference between the weight of the right side portion and the weight of the left side portion of the shaft 50 formed integrally with the rotor body 530 is eliminated and the vertical center is not biased. Deploy. With respect to the vertical direction, the balance weights 62a and 62b are disk-shaped as described above, so that the centers thereof are arranged on the first straight line X-X '. On the other hand, the left and right directions are arranged so as to be line symmetric with respect to the second straight line Y-Y ′.

  Next, the weight of the balance weights 62a and 62b will be described. When the shaft 50 configured integrally with the rotor body 530 and the shaft 50 configured integrally with the rotor body 530 ′ are compared, the difference between the weight of the right portion and the weight of the left portion in the former is the right portion of the latter. Is smaller than the difference between the weight of the left part and the weight of the left part. Accordingly, since the balance weight is provided to eliminate the difference between the weight of the right side portion and the weight of the left side portion, the total weight of the balance weights 62a and 62b when the sound absorption chamber 54b is formed is equal to the sound absorption chamber 54b. This is lighter than the total weight of the balance weights 62a ′ and 62b ′ when no is formed.

(Characteristics of the compressor according to the second embodiment)
The compressor according to the second embodiment has the following characteristics.

  In the compressor of the second embodiment, when the shaft 50 configured integrally with the rotor body 530 and the shaft 50 configured integrally with the rotor body 530 ′ are compared, the weight of the right portion and the weight of the left portion in the former are compared. Is smaller than the difference between the weight of the right part and the weight of the left part in the latter. Therefore, the total weight of the balance weights 62a and 62b when the sound absorbing chamber 54b is formed may be lighter than the total weight of the balance weights 62a ′ and 62b ′ when the sound absorbing chamber 54b is not formed. It becomes possible. Accordingly, the cost of the balance weight can be reduced, so that the manufacturing cost of the compressor can also be reduced.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  In the above embodiment, one or two Helmholtz type sound absorbing chambers are provided in the rotor body, but the present invention is not limited to this. For example, the rotor body 531 shown in FIG. Four sound absorbing chambers 54a to 54d may be provided at intervals. In addition, since these sound absorption chambers 54a-54d are arrange | positioned inside magnet 60a-60d, it is possible to reduce a noise, without reducing the efficiency of a motor.

  In the above embodiment, four magnets are provided on the rotor body. However, the present invention is not limited to this, and for example, three sound absorbing chambers at intervals of 120 ° with respect to the rotation axis O as in the rotor body 532 shown in FIG. 54e to 54g may be provided, and six magnets 62a to 62f may be provided at intervals of 60 ° with respect to the rotation axis O. Moreover, the sound absorbing chambers 54e to 54g may be provided with a shape different from that of the sound absorbing chambers 54a to 54d, thereby reducing noise having a frequency different from that of the sound absorbing chambers 54a to 54d. In addition to this, for example, one sound absorbing chamber 54e and six magnets 62a to 62f may be provided as in a rotor body 533 shown in FIG.

  Moreover, in the said embodiment, although the four plate-shaped magnets 60a-60d were embed | buried under the rotor, it is not limited to this, For example, as shown in FIG. 9, it has a diameter smaller than the diameter of the rotor main body 534. Two magnets 63a and 63b having a substantially semi-cylindrical shape may be embedded.

  If this invention is utilized, it will become possible to reduce the noise of a compressor, without reducing compression efficiency.

DESCRIPTION OF SYMBOLS 1 Compressor 20 Motor 30 Compression mechanism 50 Shaft 50a Crankshaft 50b Eccentric part 51 Rotor 52 Stator 53, 530-534 Rotor main body 53a Rotor lower surface 54a-54f Sound absorption chamber (Helmholtz type)
541a, 541b Sound absorption chamber opening 542a, 542b Resonance chamber 60a-60d, 62a-62f, 63a-63b Magnet B1 Primary space

Claims (5)

A sealed container;
A drive mechanism housed in the hermetic container and having a rotor and a stator disposed radially outside the rotor;
On the lower surface of the rotor, a sound absorption chamber serving as a Helmholtz resonator is provided.
A compressor characterized by that. The rotor has a magnet extending along its axial direction;
The sound absorbing chamber is disposed inside the magnet in a plan view.
The compressor according to claim 1. A plurality of sound absorbing chambers are provided on the lower surface of the rotor,
The plurality of sound absorption chambers are arranged at substantially equal angular intervals with respect to the rotation axis of the rotor in plan view.
The compressor according to claim 1 or 2, characterized by the above-mentioned. The drive mechanism is
A crankshaft penetrating the center of the rotor;
An eccentric portion provided on the crankshaft,
The sound absorbing chamber is disposed symmetrically with respect to a first straight line passing through the center of the crankshaft and the center of the eccentric portion in plan view.
The compressor according to any one of claims 1 to 3, wherein the compressor is provided. The drive mechanism is
A crankshaft penetrating the center of the rotor;
An eccentric portion provided on the crankshaft,
The sound-absorbing chamber is arranged in symmetry with respect to a second straight line that is perpendicular to a first straight line that passes through the center of the crankshaft and the center of the eccentric portion in a plan view and that passes through the center of the crankshaft. ing,
The compressor according to any one of claims 1 to 4, wherein the compressor is provided.

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