JP4513633B2 - Compressor - Google Patents

Description

  The present invention relates to a compressor used in, for example, an air conditioner or a refrigerator.

  2. Description of the Related Art Conventionally, there is a compressor provided with an axial gap type motor arranged in order from the top to the bottom in a sealed container and a compression section driven by this motor (Japanese Patent Laid-Open No. 61-185040). Publication: see Patent Document 1).

  The motor is arranged in an atmosphere of high-pressure refrigerant discharged from the compression unit. That is, this compressor is a so-called high-pressure dome type. Further, lubricating oil for lubricating the bearings and the like is stored below the compression portion in the closed container.

However, in the conventional compressor, since the lubricating oil is stored below the compression portion, a space for storing the lubricating oil is required below the sealed container. There is a disadvantage that the total length of the compressor becomes large. Further, since the motor is cooled by the refrigerant, a portion that is difficult to be cooled by the flow of the refrigerant occurs.
JP-A 61-185040

  Therefore, an object of the present invention is to provide a compressor that can effectively cool a motor and can be downsized.

In order to solve the above problems, a compressor according to the present invention includes an axial gap type motor arranged in order from the bottom in a sealed container, and a compression unit driven by the motor,
The motor includes a stator having a coil, a rotor disposed on the stator via an air gap, and a transmission mechanism fixed to the rotor and transmitting the rotational force of the rotor to the compression unit. And
The airtight container has a lubricating oil in which at least a part of the stator is immersed.

  Here, the upper side means the upper side along the central axis of the closed container regardless of whether the central axis of the closed container is inclined with respect to the horizontal plane.

  According to the compressor of the present invention, since the lubricating oil immerses at least a part of the stator, the stator (particularly the coil) that is a main heat source of the motor can be cooled by the lubricating oil.

  Thus, the lubricating oil that lubricates bearings and the like can be used for cooling the stator. Further, unlike the radial gap motor, since the lubricating oil does not contact the rotating rotor, it is possible to prevent an increase in input due to stirring loss. Furthermore, the space for storing the lubricating oil becomes unnecessary, and the overall length of the compressor can be reduced.

  Moreover, in the compressor of one Embodiment, the oil level of the said lubricating oil is located between the lower end and upper end of the said stator.

  In one embodiment of the compressor, the motor is disposed in a region in the sealed container that is filled with a low-pressure refrigerant to be sucked into the compression unit, and the sealed container is in the vicinity of the rotor of the motor. A suction pipe that opens to the top.

  According to the compressor of this embodiment, since the closed container has a suction pipe that opens in the vicinity of the rotor of the motor, the refrigerant sucked into the sealed container from the suction pipe is brought into contact with the rotor. The rotor can be cooled.

  In the compressor according to an embodiment, the motor is arranged in a region in the hermetic container where the low-pressure refrigerant to be sucked into the compression unit is filled, and torque detection for detecting the torque of the rotor of the motor. Department.

  According to the compressor of this embodiment, in a low-pressure dome type compressor, in the case of liquid back, the oil level of the lubricating oil rises and reaches the rotor, and the torque of the rotor increases. By detecting the torque of the rotor at this time by the torque detector, the liquid back can be easily determined.

  In the compressor according to an embodiment, the motor is disposed in a region in the sealed container filled with the high-pressure refrigerant discharged from the compression unit, and the sealed container is located above the rotor of the motor. A discharge pipe that opens to the top.

  According to the compressor of this embodiment, the airtight container has a discharge pipe that opens above the rotor of the motor. Therefore, even when the rotor stirs the lubricating oil, the lubricating oil Outflow from the discharge pipe is prevented.

  In the compressor according to an embodiment, the motor is disposed in a region in the sealed container filled with the high-pressure refrigerant discharged from the compression unit, and the compression unit is a discharge opening in the vicinity of the motor. It has a gas passage outlet.

  According to the compressor of this embodiment, since the compression unit has the discharge gas passage outlet that opens in the vicinity of the motor, the motor is efficiently cooled by the refrigerant discharged from the compression unit. can do.

  In one embodiment, the transmission mechanism is a shaft, and the stator has a bearing that supports the shaft.

  According to the compressor of this embodiment, since the stator has the bearing, a space for providing the bearing becomes unnecessary, and the overall length of the compressor can be further reduced. Further, since the stator is immersed in the lubricating oil, it is convenient for supplying oil to the bearing.

  Moreover, in the compressor of one Embodiment, the said stator has a hole part which contacts the said lubricating oil.

  According to the compressor of this embodiment, since the stator has a hole portion that comes into contact with the lubricating oil, an area where the stator comes into contact with the lubricating oil is increased, and the cooling effect of the motor is further increased. To do. Further, since the shaft having a large diameter is not immersed in the lubricating oil, oil stirring loss due to the shaft can be prevented.

  According to the compressor of the present invention, since the lubricating oil immerses at least a part of the stator, the motor can be cooled effectively and the size can be reduced.

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

(First embodiment)
FIG. 1 is a longitudinal sectional view showing an embodiment of the compressor of the present invention. The compressor includes an axial gap type motor 2 and a compression unit 3 driven by the motor 2, which are disposed in the sealed container 1 in order from the bottom to the top. Here, the upper side means the upper side along the central axis of the sealed container 1 regardless of whether or not the central axis of the sealed container 1 is inclined with respect to the horizontal plane.

  The motor 2 is disposed in a region in the sealed container 1 where a low-pressure refrigerant to be sucked into the compression unit 3 is filled. Specifically, the sealed container 1 is partitioned into a high pressure region H and a low pressure region L with the compression unit 3 interposed therebetween, and the motor 2 is disposed in the low pressure region L. This compressor is a so-called low-pressure dome type.

  The motor 2 includes a stator 21, a rotor 26 disposed on the stator 21 via an air gap, and a transmission that is fixed to the rotor 26 and transmits the rotational force of the rotor 26 to the compression unit 3. Mechanism G. The transmission mechanism G is a shaft 20.

  As shown in FIGS. 1, 2, and 3, the stator 21 includes an iron core 23 attached to the sealed container 1 and a coil 22 attached to the iron core 23.

  The iron core 23 has an annular base 24a disposed so as to be substantially orthogonal to the shaft 20, and a protrusion 24b provided on one surface of the base 24a on the rotor 26 side.

  The protrusions 24 b extend along the shaft 20, and a plurality of the protrusions 24 b are provided around the shaft 20. The coil 22 is wound around the axis of each protrusion 24b. The coil 22 is excited to generate a magnetic flux in the axial direction of the protrusion 24b.

  The stator 21 has a stator plate 25 that sandwiches the coil 22 in cooperation with the iron core 23. The stator plate 25 is made of a magnetic material, and is provided with slits 25a that magnetically insulate between the adjacent protrusions 24b. The slits 25a extend radially outward from the center of the stator plate 25 in the radial direction. With this configuration, the stator core area facing the air gap increases, so that the flux linkage can be increased. The stator plate 25 is not essential.

  The rotor 26 includes an annular back yoke 28 attached to the shaft 20, and a permanent magnet 27 provided on one surface of the back yoke 28 on the stator 21 side.

  The back yoke 28 is made of a magnetic material. The permanent magnet 27 has different magnetic poles alternately in the circumferential direction of the shaft 20. The permanent magnet 27 generates a magnetic flux in a direction along the shaft 20.

  The permanent magnet 27 has a plurality of magnets having one magnetic pole, and the plurality of magnets are arranged so that the magnetic poles are alternately different in the circumferential direction of the shaft 20. A space 27a is formed between the adjacent magnets.

  Since the rotor 26 includes the permanent magnet 27, when the motor 2 is stopped, the rotor 26 can be attracted to the stator 21 to prevent reverse rotation of the rotor 26 and the shaft 20. Moreover, since the magnetic flux density of the air gap can be increased during the operation of the motor 2, high output and high efficiency of the compressor can be realized. The permanent magnet 27 is not essential.

  The rotor 26 has a rotor plate 29 that sandwiches the permanent magnet 27 in cooperation with the back yoke 28. The rotor plate 29 is made of a magnetic material, and is provided with a slit 29 a that magnetically insulates between the adjacent magnetic poles of the permanent magnet 27. The slits 29a extend radially outward from the center of the rotor plate 29 in the radial direction. With this configuration, the area of the rotor core facing the air gap increases, so that the flux linkage can be increased. Further, since the demagnetizing field is not directly applied to the permanent magnet 27, the demagnetization resistance is also increased. The rotor plate 29 is not essential.

  The compression unit 3 includes a main body 30 attached to the sealed container 1, a fixed scroll 31 fixed and supported by the main body 30, and a turning scroll 32 that meshes with the fixed scroll 31.

  The fixed scroll 31 has a spiral wrap on the end plate, and meshes with the orbiting scroll 32 to form a plurality of compression chambers 33. The orbiting scroll 32 is attached to one end of the shaft 20 of the motor 2 and revolves as the shaft 20 rotates.

  The main body 30 is inserted through the shaft 20 and supports one end side of the shaft 20 via the bearing 4. A holding portion 5 is attached to the inside of the sealed container 1 below the motor 2, and the other end side of the shaft 20 is supported by the holding portion 5 via a bearing 4. That is, the shaft 20 is both supported. The bearing 4 is a sliding bearing, for example.

  The main body 30 has a suction hole 30 a that communicates the low pressure region L and the compression chamber 33, and the fixed scroll 31 has a discharge hole 31 a that communicates the high pressure region H and the compression chamber 33. .

  The sealed container 1 has a suction pipe 6 that opens in the vicinity of the rotor 26 of the motor 2. Specifically, the suction pipe 6 opens at the same height as the rotor 26. The opening of the suction pipe 6 faces the rotor 26 side. The sealed container 1 has a discharge pipe 7 that opens to the high-pressure region H.

  A lubricating oil 8 in which at least a part of the stator 21 is immersed is provided on the lower side of the sealed container 1. That is, the oil surface 8a of the lubricating oil 8 is located between the lower end and the upper end of the stator 21, and more specifically, the oil surface 8a is at least in a position where the coil 22 is immersed. Further, the other end side of the shaft 20 is immersed in the lubricating oil 8. The lubricating oil 8 goes up inside the shaft 20 by the rotation of the shaft 20 and lubricates the sliding portion of the compression portion 3, the bearing 4 and the like.

  The compressor includes a torque detector 9 that detects the torque of the rotor 26 of the motor 2.

  Next, the operation of the compressor will be described.

  The refrigerant sucked into the sealed container 1 from the suction pipe 6 strikes the rotor 26 and cools the rotor 26. At this time, since the rotor 26 is rotating, the entire circumference of the rotor 26 is cooled evenly.

  The refrigerant mainly cools the rotor 26 and then is sucked into the compression chamber 33 from the suction hole 30a, is compressed by the operation of the motor 2, and is sealed from the discharge pipe 7 through the discharge hole 31a. It is discharged to the outside of the container 1.

  According to the compressor having the above configuration, the lubricating oil 8 immerses a part of the stator 21, so that the stator 21 (particularly the coil 22) that is the main heat source of the motor 2 is replaced with the lubricating oil 8. Can be cooled by. In particular, since the coils 22 of all phases are almost evenly immersed in the lubricating oil 8, the cooling effect of the coils 22 is substantially uniform depending on the phases. Therefore, for example, changes due to the temperature of the winding resistance are uniform and suitable.

  Even if the central axis of the closed container 1 is inclined with respect to the horizontal plane, the same effect can be obtained if the oil level 8a is in the position described above. Further, unlike the radial gap type motor, even when the stator 21 is immersed in the lubricating oil 8, the rotating rotor 26 does not contact the lubricating oil 8, so that there is no increase in input due to agitation loss.

  Further, since the lubricating oil 8 is used for cooling the stator 21, the refrigerant in the low pressure region L is not sufficiently heated by the stator 21.

  Thus, the lubricating oil 8 that lubricates the bearings 4 and the like can be used for cooling the stator 21. Moreover, the space for storing the lubricating oil 8 is not necessary, and the overall length of the compressor can be reduced.

  Here, in this low-pressure dome type compressor, the oil level 8a of the lubricating oil 8 rises and reaches the rotor 26 as shown by the phantom line in FIG. At this time, the torque of the rotor 26 suddenly increases. That is, since the outer diameter of the rotor 26 is large, the torque for stirring the lubricating oil 8 is increased.

  Then, by detecting the torque of the rotor 26 by the torque detector 9, the liquid back can be easily determined. Further, after the torque detection unit 9 determines the liquid back, the motor 2 can be stopped, or control for reducing the rotational speed of the motor 2 can be performed.

  Specifically, the torque fluctuation due to the pressure change is estimated, and a torque fluctuation exceeding a certain threshold is detected from the torque (which is constant) that cancels the torque fluctuation, thereby determining the liquid back. When it is determined that the liquid is back, a microcomputer (not shown) of the compressor body is notified so as to perform control such as stopping the motor or lowering the rotational speed of the motor. At the same time, measures such as increasing the target value of SH control may be taken.

  Here, the SH control refers to super heat control. Therefore, the target value is to set the superheat degree of a certain part to that value. For example, when the indoor unit is being cooled, the degree of superheat at the heat exchange outlet (evaporator outlet) is controlled, while when the indoor unit is being heated, the suction superheat degree of the compressor is controlled. In this way, by increasing the target value for SH control, wet refrigerant does not enter the compressor, so liquid compression is avoided and the compressor is safe.

(Second Embodiment)
FIG. 4 shows a second embodiment of the compressor of the present invention. The difference from the first embodiment will be described. In the second embodiment, the shaft 20 is cantilevered only on one end side and supported by the bearing 4. An oil pickup 10 is provided on the other end side of the shaft 20. The oil pickup 10 is immersed in the lubricating oil 8 and rotates with the rotation of the shaft 20, and the lubricating oil 8 is supplied to each sliding portion using a centrifugal force generated by the rotation. . According to this configuration, the end portion of the shaft 20 is not immersed in the lubricating oil 8 or even if immersed in the lubricating oil 8, the length of the shaft 20 in the immersed portion is short. Loss can be kept low.

(Third embodiment)
FIG. 5 shows a third embodiment of the compressor of the present invention. The difference from the first embodiment will be described. In the third embodiment, instead of the holding portion 5 of the first embodiment (FIG. 1), the stator 21 is formed of the shaft 20. It has a bearing 4 that supports the other end side. The bearing 4 is provided inside the stator 21. The bearing 4 is, for example, a rolling bearing. Since this rolling bearing receives both axial loads in the thrust direction and radial direction, it is not necessary to provide both a thrust bearing and a journal bearing.

  Thus, since the stator 21 has the bearing 4, a space for providing the bearing becomes unnecessary, and the overall length of the compressor can be further reduced. Further, since the stator 21 is immersed in the lubricating oil 8 (see FIG. 1), it is convenient for supplying oil to the bearing 4. The bearing 4 is held by being press-fitted into a recess provided in the iron core 23 of the stator 21.

  Further, the stator 21 has a hole 21 a that contacts the lubricating oil 8. That is, the hole 21 a is provided on the lower surface of the base 24 a of the iron core 23. A hole that penetrates the stator 21 may be provided.

  Thus, since the stator 21 has the hole 21a that contacts the lubricating oil 8, the area where the stator 21 contacts the lubricating oil 8 is increased, and the cooling effect of the motor 2 is further increased. To do. Further, since the iron core 23 has a low thermal resistance and a high magnetic permeability, providing the hole 21a so as not to be magnetically saturated is suitable both in terms of magnetic and cooling performance.

(Fourth embodiment)
FIG. 6 shows a fourth embodiment of the compressor of the present invention. The difference from the first embodiment will be described. In the fourth embodiment, the motor 2 is arranged in a region in the sealed container 1 where the high-pressure refrigerant discharged from the compression unit 11 is filled. ing. Specifically, the inside of the sealed container 1 is a high-pressure region H, and this compressor is a so-called high-pressure dome type.

  The compression unit 11 includes a cylindrical main body 12 and an upper end plate 15 and a lower end plate 16 that are attached to upper and lower open ends of the main body 12, respectively. The shaft 20 penetrates the upper end plate 15 and the lower end plate 16 and enters the main body 12.

  A roller 13 fitted to a crankpin 17 provided on the shaft 20 is disposed inside the main body portion 12 so as to be able to revolve, and a compression action is performed by the revolving motion of the roller 13. That is, a compression chamber 14 is formed between the outer surface of the roller 13 and the inner surface of the main body portion 12.

  The suction pipe 6 communicates with the compression chamber 14 of the compression unit 11. The discharge pipe 7 is opened above the rotor 26 of the motor 2. That is, the discharge pipe 7 is open above the compression unit 11.

  The compression unit 11 has a discharge gas passage outlet 35 that opens in the vicinity of the motor 2. That is, the discharge gas passage outlet 35 is a discharge hole 11 a that opens to face the motor 2.

  Next, the operation of the compressor will be described.

  A refrigerant is supplied from the suction pipe 6 to the compression chamber 14 of the compression unit 11, and the compression unit 11 is driven by the motor 2 to compress the refrigerant. The compressed refrigerant is discharged into the hermetic container 1 from the discharge hole 11a of the compression unit 11, and after cooling the rotor 26 mainly, passes through the space on the outer periphery of the compression unit 11 and the compression. It is carried to the upper space of the part 11 and discharged from the discharge pipe 7 to the outside of the closed container 1.

  The lubricating oil 8 immerses a part of the stator 21, and the stator 21 can be cooled by the lubricating oil 8 having a temperature lower than that of the high-pressure refrigerant, so that the cooling effect is increased.

  Moreover, since the said airtight container 1 has the said discharge pipe 7 opened above the said rotor 26 of the said motor 2, when the said rotor 26 stirs the said lubricating oil 8, the said lubricating oil 8 becomes the said discharge pipe. 7 is prevented from flowing out.

  Moreover, since the said compression part 11 has the discharge hole 11a opened to the vicinity of the said motor 2, the said motor 2 can be efficiently cooled with the refrigerant | coolant discharged from the said compression part 11. FIG. Further, since the discharge hole 11a opens downward and the discharge pipe 7 is located above the compression portion 11, the lubricating oil 8 discharged from the discharge hole 11a together with the refrigerant is directed downward. It can be prevented from flowing out of the discharge pipe 7.

  In addition, this invention is not limited to the above-mentioned embodiment. For example, the lubricating oil 8 may immerse the entire stator 21. Further, the motor 2 may have another stator on the rotor 26. Thereby, the thrust force of the motor 2 can be balanced. At this time, the upper stator cannot be cooled by the lubricating oil 8.

  Moreover, the motor used for this compressor is an axial gap type motor, and the form of the motor is not limited as long as the positional relationship between the stator and the rotor satisfies a predetermined condition. That is, in a steady state (meaning excluding liquid back), the lubricant may be immersed in the stator but not in the rotor.

  Further, the transmission mechanism that is fixed to the rotor and transmits the rotational force of the rotor to the compression unit may not be a shaft. For example, in the case of a rotary compressor, a roller (movable of the compression mechanism unit directly) It is also possible to provide a portion), and the rotor may act as a roller as it is.

  Further, the discharge gas passage outlet 35 may be an outlet of another passage connected to the discharge hole of the compression unit. That is, the refrigerant may be discharged once from the discharge hole on the side opposite to the motor of the compression unit and then flow out to the vicinity of the motor through another passage.

  In addition, the low pressure dome type has been described with the scroll type compression mechanism, and the high pressure dome type has been described with the rotary type compression mechanism. However, the low pressure dome type may be a combination of the rotary type compression mechanism, or the high pressure dome type may be a scroll type compression mechanism. Also good. Other types of compression mechanisms may also be used.

1 is a longitudinal sectional view showing a first embodiment of a compressor of the present invention. It is an expanded vertical sectional view of the principal part. It is a disassembled perspective view of a motor. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the compressor of this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the compressor of this invention. It is a longitudinal cross-sectional view which shows 4th Embodiment of the compressor of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Motor 3 Compression part 4 Bearing 6 Suction pipe 7 Discharge pipe 8 Lubricating oil 8a Oil level 9 Torque detection part 10 Oil pick-up 11 Compression part 11a Discharge hole 12 Body part 13 Roller 14 Compression chamber 20 Shaft 21 Stator 21a Hole part 22 Coil 23 Iron Core 26 Rotor 27 Permanent Magnet 28 Back Yoke 30 Main Body 30a Suction Hole 31 Fixed Scroll 31a Discharge Hole 32 Orbiting Scroll 33 Compression Chamber 35 Discharge Gas Path Exit G Transmission Mechanism H High Pressure Area L Low Pressure Area

Claims (8)

Arranged in order from bottom to top in the sealed container (1),
An axial gap type motor (2);
A compression section (3, 11) driven by the motor (2),
The motor (2)
A stator (21) having a coil (22);
A rotor (26) disposed on the stator (21) via an air gap;
A transmission mechanism (G) fixed to the rotor (26) and transmitting the rotational force of the rotor (26) to the compression section (3, 11);
A compressor having a lubricating oil (8) in which at least a part of the stator (21) is immersed in the sealed container (1). The compressor according to claim 1,
The compressor characterized in that the oil surface (8a) of the lubricating oil (8) is located between a lower end and an upper end of the stator (21). The compressor according to claim 1,
The motor (2) is disposed in a region in the sealed container (1) that is filled with a low-pressure refrigerant to be sucked into the compression unit (3),
The compressor, wherein the closed container (1) has a suction pipe (6) opened in the vicinity of the rotor (26) of the motor (2). The compressor according to claim 1,
The motor (2) is disposed in a region in the sealed container (1) that is filled with a low-pressure refrigerant to be sucked into the compression unit (3),
A compressor comprising a torque detector (9) for detecting the torque of the rotor (26) of the motor (2). The compressor according to claim 1,
The motor (2) is disposed in a region in the sealed container (1) filled with the high-pressure refrigerant discharged from the compression unit (11),
The compressor, characterized in that the sealed container (1) has a discharge pipe (7) that opens above the rotor (26) of the motor (2). The compressor according to claim 1,
The motor (2) is disposed in a region in the sealed container (1) filled with the high-pressure refrigerant discharged from the compression unit (11),
The compressor characterized in that the compression section (11) has a discharge gas passage outlet (35) opened in the vicinity of the motor (2). The compressor according to claim 1,
The transmission mechanism (G) is a shaft (20),
The compressor (21), wherein the stator (21) has a bearing (4) for supporting the shaft (20). The compressor according to claim 1,
The compressor (21), wherein the stator (21) has a hole (21a) in contact with the lubricating oil (8).

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