JP2014107947A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor for reducing a vibration of a casing and suppressing a noise.SOLUTION: Provided is a casing and a stator 51. The casing includes a cylindrical pipe 21. The stator 51 is fixed by shrink fitting on an inner peripheral surface of the pipe 21 with a cutout 56 being formed on an outer peripheral edge. The stator 51 is formed by laminating a plurality of magnetic steel sheets 53. The stator 51 has an outer peripheral edge whose cross sectional shape before the cutout 56 is formed is a protruded simple close curve that is different from a circle. Moreover, the stator 51 is in contact with an inner peripheral surface of the pipe 21 at a multiple portions of the outer peripheral edge while being fixed to the pipe 21.

Description

  The present invention relates to a compressor.

  Conventionally, there is a compressor in which a stator is fixed to the inner peripheral surface of a cylindrical pipe by shrink fitting. The stator is formed by laminating electromagnetic steel sheets as disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2010-288330).

  Generally, a rotor in which a permanent magnet is fitted is located on the inner peripheral side of the stator. A winding is wound around the tooth portion, and when the winding is energized, a rotating magnetic field is generated between the stator and the rotor, so that the motor rotates.

  During operation of the motor, the stator vibrates due to the attractive force and repulsive force generated between the permanent magnet of the rotor and the stator. When the stator vibrates, depending on the number of rotations, the casing including the pipe to which the stator is fixed causes resonance vibration. It is preferable that the situation can be suppressed because the casing causes resonance vibration, which leads to generation of noise.

  Therefore, in Patent Document 1, in order to suppress the vibration of the stator from propagating to the pipe, a notch is formed on the outer peripheral surface of the stator, and the notch is provided so as not to be rotationally symmetric in the circumferential direction. Yes.

  However, the stator disclosed in Patent Document 1 is configured such that its outer diameter is substantially the same as the inner diameter of the pipe. For this reason, even if the notch is formed as described above, the state of contact between the pipe and the stator does not change during vibration, and it is considered that a sufficient vibration attenuation rate cannot be obtained. Therefore, in the stator of Patent Document 1, it is still considered that the casing easily resonates with the vibration of the stator.

  Then, the subject of this invention is providing the compressor which reduces the vibration of a casing and suppresses a noise.

  A compressor according to a first aspect of the present invention includes a casing and a stator. The casing includes a cylindrical pipe. The stator is fixed by shrink fitting on the inner peripheral surface of the pipe with a notch formed in the outer peripheral edge, and is formed by stacking a plurality of electromagnetic steel sheets. Further, the stator has an outer peripheral edge of a convex simple closed curve whose cross-sectional shape before the notch is formed is different from the circle. In addition, the stator is in contact with the inner peripheral surface of the pipe at a plurality of locations on the outer peripheral edge in a state of being fixed to the pipe.

  In the compressor according to the first aspect of the present invention, in a state where the stator has the outer peripheral edge of the convex simple closed curve and the cross-sectional shape before the notch is formed is fixed to the pipe, The outer peripheral edge is configured to contact the inner peripheral surface of the pipe at a plurality of locations. Thereby, when the casing including the pipe causes resonance vibration due to the vibration of the stator, the contact portion between the pipe and the stator slightly moves in the vicinity of the contact point, and the vibration damping rate is increased. Therefore, since the vibration of the casing can be reduced, noise can be suppressed.

  The compressor which concerns on the 2nd viewpoint of this invention is a compressor which concerns on the 1st viewpoint of this invention, Comprising: As for several electromagnetic steel plates, the contact location in planar view with the internal peripheral surface of each pipe shifts | deviates. Are stacked.

  In the compressor according to the second aspect of the present invention, the electromagnetic steel plates are laminated so that the contact portions in plan view with the inner peripheral surface of the pipe are displaced, so that the support supported by the stator pipe in the lamination direction The position is different. Thereby, the stability and balance of the stator can be improved.

  The compressor which concerns on the 3rd viewpoint of this invention is a compressor which concerns on the 1st viewpoint or 2nd viewpoint of this invention, Comprising: The cross-sectional shape before the notch of a stator is formed is an elliptical shape.

  In the compressor according to the third aspect of the present invention, the vibration of the casing can be reduced and noise can be suppressed.

  The compressor which concerns on the 4th viewpoint of this invention is a compressor which concerns on either of the 1st viewpoint of this invention-the 3rd viewpoint, Comprising: The contact location of the stator and the internal peripheral surface of a pipe is three or more points. is there.

  In the compressor according to the fourth aspect of the present invention, since the number of contact points between the stator and the inner peripheral surface of the pipe is three or more, it is easy to maintain the balance of the stator.

  In the compressor according to the first aspect of the present invention, the vibration of the casing can be reduced and noise can be suppressed.

  In the compressor according to the second aspect of the present invention, the stability and balance of the stator can be improved.

  In the compressor according to the third aspect of the present invention, the vibration of the casing can be reduced and noise can be suppressed.

  In the compressor according to the fourth aspect of the present invention, it is easy to maintain the balance of the stator.

The schematic longitudinal cross-sectional view of a compressor. The schematic cross-sectional view of the compression element of a compressor. The figure which looked at the stator of the state in which the notch is not formed from the axial direction upper side. The figure which looked at the stator and the pipe of the casing from the axial direction upper side in order to show a notch line. The figure which looked at the stator after a notch was formed, and a pipe from the axial direction upper side. The figure which shows the lamination | stacking state of an electromagnetic steel plate for showing an example of the lamination | stacking method of the electromagnetic steel plate which concerns on the modification A. The figure which looked at the stator of the state where the notch is not formed, and the pipe of a casing from the axial direction upper side in order to explain the cross-sectional shape of the stator concerning modification B. The figure which looked at the stator after the notch was formed, and the pipe of a casing from the axial direction upper side in order to explain the cross-sectional shape of the stator concerning modification B.

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

(1) Overall Configuration of Compressor 1 FIG. 1 is a schematic longitudinal sectional view of the compressor 1. FIG. 2 is a schematic cross-sectional view of the compression element 3 of the compressor 1. In the following description, the vertical direction means an axial direction along a center axis O of a rotating shaft 15 (to be described later) shown in FIG. 1 (hereinafter simply referred to as “center axis O” as appropriate). A direction orthogonal to the axial direction is a radial direction, and a direction around the axial direction is a circumferential direction. Moreover, the cross section demonstrated below means the cross section at the time of cut | disconnecting perpendicularly | vertically with respect to an axial direction.

  The compressor 1 is an oscillating piston type rotary compressor that is connected to a refrigerant circuit that performs refrigeration cycle operation such as an air conditioner and compresses refrigerant as working gas.

  As shown in FIG. 1, the compressor 1 mainly includes a casing 2, a compression element 3, and a motor 5. The compressor 1 has a sealed structure in which a compression element 3 and a motor 5 are accommodated in a casing 2. Hereinafter, these configurations will be described.

(1-1) Casing 2
The casing 2 is a vertical cylindrical container, and mainly includes a substantially cylindrical pipe 21, and a substantially bowl-shaped upper end plate 22 and a lower end plate 23 that close upper and lower opening ends of the pipe 21.

  The casing 2 is provided with a suction pipe 11 and a discharge pipe 12. The suction pipe 11 is a tubular member that penetrates the lower portion of the pipe 21 and is connected to an accumulator (not shown). The suction pipe 11 introduces refrigerant gas before compression into the compression element 3 from the outside of the casing 2. The discharge pipe 12 is a tubular member that penetrates the upper end plate 22 and is connected to a refrigerant pipe (not shown) that constitutes a refrigerant circuit. The discharge pipe 12 discharges the compressed refrigerant gas from the high-pressure space SP1 to the outside of the casing 2. The accumulator is a vertical cylindrical airtight container, and the lower end of the suction pipe 11 is connected to the lower end, and the lower end of a return pipe (not shown) is connected to the upper end. The return pipe is for guiding the refrigerant circulating in the refrigerant circuit to the accumulator, and its upper end is configured to be connectable to a refrigerant pipe (not shown) constituting the refrigerant circuit.

  The upper end plate 22 is provided with a terminal 13 that is connected to an external power source and supplies power to the motor 5.

  An oil storage portion P that is a portion for storing lubricating oil is formed in the bottom portion of the casing 2. Lubricating oil is used to keep the lubricity of sliding parts such as the compression element 3 good during the operation of the compressor 1.

(1-2) Compression element 3
The compression element 3 is immersed in the lubricating oil stored in the oil storage part P. The compression element 3 mainly includes a cylinder 31, a piston 32, and a muffler 26, and is disposed in a lower portion of the space in the pipe 21. ing.

(1-2-1) Cylinder 31
The cylinder 31 is fixed to the pipe 21 of the casing 2 and mainly includes a cylinder body 33, a front head 34, and a rear head 35. The front head 34, the cylinder body 33, and the rear head 35 are arranged side by side in this order from the top in the axial direction, and are assembled together by fastening with bolts (not shown).

  As shown in FIG. 2, the cylinder body 33 is disposed concentrically with the pipe 21 of the casing 2. The cylinder body 33 is formed with a cylinder hole 33a, a suction hole 33b, and a discharge passage 33c. As for the cylinder hole 33a, the cross-sectional shape of the hole formation part 133a which forms this has a substantially circular shape. A cross section penetrating in the thickness direction of the cylinder body 33 is a substantially circular hole. The suction hole 33 b is a hole that penetrates from the outer peripheral surface of the cylinder main body 33 to the inner peripheral surface of the cylinder main body 33. The discharge path 33 c is formed by cutting out a part of the inner peripheral surface of the cylinder body 33. The cylinder body 33 is arranged so that the discharge path 33c faces the front head 34 side.

  The front head 34 and the rear head 35 are respectively formed with shaft holes 34a and 35a (see FIG. 1) penetrating the center in the axial direction.

  A compression chamber 37 is formed in the cylinder 31 by the inner peripheral surface of the cylinder body 33, the lower end surface of the front head 34, the upper end surface of the rear head 35, and the outer peripheral surface of the piston 32. The compression chamber 37 is partitioned into a suction chamber that communicates with the suction hole 33b and a discharge chamber that communicates with the discharge passage 33c.

(1-2-2) Piston 32
The piston 32 is disposed in the cylinder 31, and includes a cylindrical roller portion 32a and a blade portion 32b that protrudes radially outward from the roller portion 32a.

  The roller portion 32a is fitted into the eccentric cam 15a of the rotating shaft 15 so as to rotate integrally with the eccentric cam 15a. Therefore, the roller portion 32a revolves around the rotation shaft 15 when the rotation shaft 15 rotates.

  The rotary shaft 15 is disposed so as to extend along the center axis O of the center of the pipe 21, and is rotatably fitted in the shaft holes 34a and 35a. That is, the front head 34 and the rear head 35 function as bearings that rotatably support the lower portion of the rotating shaft 15.

  The blade part 32b advances and retreats in the longitudinal direction with the revolution of the roller part 32a.

(1-2-3) Muffler 26
As shown in FIG. 1, the muffler 26 is a member disposed so as to cover a part of the upper surface of the front head 34 around the rotary shaft 15 with the central portion of the upper surface thereof penetrating the rotary shaft 15. It is. The muffler 26 forms a muffler space SP2 in which refrigerant gas discharged from the discharge path 33c of the cylinder body 33 is stored between the muffler 26 and the upper surface of the front head 34. A muffler discharge hole 26a for discharging the refrigerant gas in the muffler space SP2 to the high-pressure space SP1 is formed on the upper surface of the muffler 26. The muffler discharge hole 26a is formed around the rotation shaft 15, and has a circular cross-sectional shape.

(1-3) Motor 5
The motor 5 is accommodated in the casing 2 and arranged above the compression element 3. As shown in FIG. 1, the motor 5 mainly has a rotor 51 in which a permanent magnet made of, for example, a rare earth magnet is fitted, and an annular stator 52 positioned on the outer peripheral side of the rotor 51. In addition, the rotation speed of the motor 5 at the time of the driving | operation of the compressor 1 is several hundred rpm-several thousand rpm, for example.

(1-3-1) Rotor 51
The rotor 51 is a substantially cylindrical member, and is connected to the compression element 3 with the rotary shaft 15 fitted in the central hole 51a. The rotation shaft 15 applies a rotational driving force to the compression element 3 by rotating the rotation shaft 15 by the rotation of the rotor 51. Thereby, the compression element 3 is driven. The rotor 51 is formed by laminating a plurality of electromagnetic steel plates in the axial direction.

(1-3-2) Stator 52
FIG. 3 is a view of the stator 52 in a state where the notch 56 is not formed, as viewed from the upper side in the axial direction. FIG. 4 is a view of the stator 52 and the pipe 21 of the casing 2 as viewed from the upper side in the axial direction in order to show the notch line L1. FIG. 5 is a view of the stator 52 and the pipe 21 after the notch 56 is formed, as viewed from the upper side in the axial direction.

  The stator 52 has an annular shape, and is fixed to the inner peripheral surface of the pipe 21 by shrink fitting so that a gap t (see FIG. 1) is formed between the inner peripheral surface of the stator 52 and the outer peripheral surface of the rotor 51. Has been.

  The stator 52 is formed by laminating a plurality (for example, fifty to several hundreds) of electromagnetic steel plates 53 in the axial direction so that the wide flat portions 53a are in close contact with each other. In the present embodiment, the stator 52 is laminated so that the outer peripheral edge of each electromagnetic steel sheet 53 coincides with the outer peripheral edge of the electromagnetic steel sheet 53 adjacent in the axial direction in the axial direction.

  The electromagnetic steel sheet 53 mainly projects from an annular ring portion 54 that forms the outline of the stator 52, and radially inward from the inner peripheral surface of the ring portion 54 (specifically, toward the central axis O). A plurality of (six in this embodiment) teeth portions 55 are provided.

  A three-phase winding is mounted on the tooth portion 55, and a rotating magnetic field is generated by energizing each winding via the terminal 13. When the rotating magnetic field is generated, the permanent magnet of the rotor 51 is attracted to the rotating magnetic field, the rotor 51 is rotationally driven, and the motor 5 is rotated. Specifically, the tooth portion 55 includes a plurality of projecting portions 55a and an arc portion 55b. The protruding portion 55a is a portion that extends radially inward from the inner peripheral surface of the ring portion 54 when viewed in the axial direction. The arc portion 55b is a portion extending in an arc shape in the circumferential direction from the inner peripheral end of the protruding portion 55a.

  Further, the stator 52 is formed with an accommodation hole 52a for accommodating the rotor 51 at the center. The accommodation hole 52a is formed along the tip edge (inner peripheral edge) of the tooth portion 55 (specifically, the arc portion 55b). In addition, the virtual shape which connected the front-end edge (inner periphery) of the teeth part 55 (arc part 55b) has a radius from the center point on the center axis line O to the front-end edge of the teeth part 55 (arc part 55b). A substantially circular shape (see a portion indicated by a one-point difference line in FIG. 3) is drawn.

  The stator 52 is shrink-fitted on the inner peripheral surface of the pipe 21 with a core cut space S (see FIG. 5) formed between the outer peripheral surface of the stator 52 and the inner peripheral surface of the pipe 21. The The core cut space S is a flow path for returning the lubricating oil flowing from the compression chamber 37 to the high pressure space SP1 together with the refrigerant gas to the oil reservoir P (that is, for circulating the lubricating oil). Space. The core cut space S is usually formed by forming a notch on the outer periphery of the stator at a predetermined interval in the circumferential direction and from one end surface to the other end surface.

  Here, during operation of the motor, the stator vibrates due to the attractive force and repulsive force generated between the permanent magnet of the rotor and the stator. When the stator vibrates, depending on the number of rotations, the casing including the pipe to which the stator is fixed causes resonance vibration. For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2010-288330), a notch is formed in the outer peripheral surface of the stator, and the notch is rotated in the circumferential direction. Providing it so as not to be symmetric prevents the vibration of the stator from propagating to the pipe. However, the stator disclosed in Patent Document 1 is configured such that its outer diameter is substantially the same as the inner diameter of the pipe. For this reason, even if a notch is formed on the outer peripheral surface of the stator, it is considered that the state of contact between the pipe and the stator does not change during vibration and a sufficient vibration damping rate cannot be obtained. Therefore, in the stator of Patent Document 1, there is still a concern that the casing is likely to resonate with the vibration of the stator.

  Therefore, in this embodiment, as shown in FIGS. 3 and 4, the shape of the axial view before forming the notch 56 (see FIG. 5) has an outer peripheral edge of a convex simple closed curve different from the circle. The stator 52 is formed by laminating electromagnetic steel plates 53 (see the two-dot chain lines in FIGS. 3 and 4). Note that a convex simple closed curve is such that when two arbitrary points are taken in a portion surrounded by a convex simple closed curve, the straight line connecting the two points satisfies the condition of being located in the portion surrounded by the convex simple closed curve. A closed curve. More specifically, in the electromagnetic steel sheet 53, the vertices A, B, and C of the polygonal shape (triangle shown by the dotted line in FIG. 3 in this embodiment) in the axial direction are curves C1, C2, and C3. It is formed to have an outer peripheral edge that can be connected. Note that the curve C1 and the arc portion CA1 (see FIG. 4) with respect to the string connecting the point A and the apex B among the inner peripheral edges of the pipe 21 do not coincide with each other, and the curve C2 and the apex among the inner peripheral edges of the pipe 21 Arc portion CA2 (see FIG. 4) for the string connecting B and vertex C does not match, and arc portion CA3 (FIG. 4) for the string connecting vertex C and vertex C of the inner periphery of pipe 21 is not matched. 4). That is, the center of the virtual circle formed by extending the curve C1 does not coincide with the center of the pipe 21 (a point on the central axis O), and the center of the virtual circle formed by extending the curve C2 and the pipe 21 The center of the virtual circle formed by extending the curve C3 and the center of the pipe 21 (point on the central axis O) do not match.

  Therefore, the stator 52 formed by laminating the electromagnetic steel sheets 53 having such a shape also has an outer peripheral edge of a convex simple closed curve whose cross-sectional shape before the notch 56 is formed is not a circle. It is configured. And the notch 56 is formed in the outer peripheral surface of the stator 52 with which the electromagnetic steel plate 53 which has the above-mentioned shape was laminated | stacked from one end surface to the other end surface. Specifically, the cross-sectional shape is flat from one end surface to the other end surface along a notch line L1 that is a polygon (in this embodiment, a dodecagon) as shown by the dotted line in FIG. 4 when viewed in the axial direction. A notch 56 is formed so as to have a shape. That is, the stator 52 has an outer peripheral edge (a portion indicated by a two-dot chain line in FIGS. 3 and 4) before the notch 56 is formed in the axial direction, and a notch line L <b> 1 positioned on the inner peripheral side from this. And the part surrounded by (the hatched area in FIG. 4) is cut out.

  Further, in the present embodiment, each of the laminated electromagnetic steel plates 53 is fixed to the pipe 21 so that the outer peripheral edge and the inner peripheral surface of the pipe 21 are in contact with each other at a plurality of points when viewed in the axial direction. It is configured. In the present embodiment, the plurality of points are three points, and specifically, points corresponding to the vertices A, B, and C on the outer peripheral edge of the electromagnetic steel sheet 53. In the following, the contact points between the points corresponding to the vertices A, B, and C on the outer peripheral edge of the electromagnetic steel sheet 53 and the inner peripheral surface of the pipe 21 are referred to as contact points P1, P2, P3 ( Refer to FIG.

  Therefore, the stator 52 formed by laminating such electromagnetic steel plates 53 also makes point contact with the inner peripheral surface of the pipe 21 at a plurality of points (specifically, points P1, P2, P3) in the axial direction. It is configured as such. In other words, the outer periphery of the electromagnetic steel sheet 53, and thus the stator 52, is smaller than the inner periphery of the pipe 21. Further, the distance d1 (see FIG. 4) between the points excluding the points P1, P2, and P3 on the outer peripheral edge of the electromagnetic steel sheet 53 in the axial direction and the central axis O is the inner diameter d2 of the pipe 21 (see FIG. 4). Smaller).

  In the present embodiment, the notch 56 avoids contact points between the stator 52 and the pipe 21 (specifically, points P1, P2, P3) from the viewpoint of maintaining the stability and balance of the stator 52. It is formed as follows.

(2) Manufacturing method of compressor 1 Next, the manufacturing method of the compressor 1 is demonstrated.

  First, the pipe 21 and the stator 52 are formed. Specifically, a cylindrical pipe 21 configured by bending a plate-shaped metal member into a cylindrical shape and butt-welding the ends thereof is formed. Also, a plurality of electromagnetic steel plates 53 having an outer peripheral edge of a convex simple closed curve are prepared, and laminated so that the respective flat portions 53a are in close contact with each other and the outer peripheral edges of the respective electromagnetic steel plates 53 are coincident in the axial direction view. To do. Then, the laminated electromagnetic steel sheets 53 are caulked.

  Next, the notches 56 are formed in the plurality of crimped electromagnetic steel plates 53 so that the cross-sectional shape becomes a planar shape from one end face to the other end face along the notch line L1.

  Next, the pipe 21 is heated for about several minutes by high-frequency heating or an oven. Thereby, the pipe 21 is heated to around 300 ° C., and the outer diameter and the inner diameter thereof are expanded. Next, the heated pipe 21 is placed on the outer periphery side of the stator 52 so as to cover the outer periphery of the stator 52 (a state where the notch 56 is formed) supported by a jig (not shown).

  Thereafter, the pipe 21 is forcibly cooled from the outside by a cooling device such as a cold air blower. As a result, the outer diameter and inner diameter of the pipe 21 are contracted, and the pipe 21 is shrink-fitted onto the outer peripheral surface of the stator 52. Furthermore, the compressor 1 is manufactured by attaching components such as the rotor 51, the compression element 3, and the end plates 22 and 23 to the pipe 21 shrink-fitted into the stator 52.

(3) Operation and Flow of Refrigerant Gas By driving the motor 5, the eccentric cam 15a rotates eccentrically around the rotation shaft 15. Thereby, the roller part 32a of the piston 32 connected to the eccentric cam 15a revolves in the cylinder hole 33a in a state where the outer peripheral surface is in contact with the inner peripheral surface of the cylinder body 33. Along with the revolution in the cylinder hole 33a of the roller portion 32a, the blade portion 32b of the piston 32 advances and retreats along its longitudinal direction. As the cylinder portion 33a of the roller portion 32a revolves, the suction chamber communicating with the suction hole 33b is gradually increased in volume to become a discharge passage 33c, and the discharge chamber is gradually decreased in volume again. It becomes the suction chamber.

  As a result, as shown in FIG. 1, the low-pressure refrigerant gas sucked into the suction chamber from the suction pipe 11 via the suction hole 33b is compressed into the high-pressure refrigerant gas in the discharge chamber and then discharged from the discharge chamber. It is discharged to the muffler space SP2 via the path 33c. The refrigerant gas in the muffler space SP2 is discharged to the high-pressure space SP1 above the rotor 51 via the muffler discharge hole 26a and the gap t. Finally, the refrigerant gas is discharged to the outside of the casing 2 through the discharge pipe 12.

(4) Features (4-1)
In the present embodiment, the electromagnetic steel plates 53 having such a shape that the shape viewed in the axial direction before forming the notch 56 is the outer peripheral edge of a convex simple closed curve that is not a circle are laminated along the axial direction. Thus, the stator 52 is formed. Further, in the present embodiment, the stator 52 is configured to come into contact with the inner peripheral surface of the pipe 21 at a plurality of locations (a plurality of points) on the outer peripheral edge in a state where the stator 52 is fixed to the pipe 21 of the casing 2 by shrink fitting. Has been.

  In the present embodiment, when the casing 2 including the pipe 21 undergoes resonance vibration due to the vibration of the stator 52, the contact portion (contact point) with the inner peripheral surface of the pipe 21 is slightly around the contact point. The vibration damping rate is increased by moving in the direction.

  Therefore, the vibration damping rate can be increased as compared with a conventional stator in which the state of contact between the pipe and the stator does not change during vibration. Therefore, the resonance vibration of the casing 2 can be reduced and noise can be suppressed.

(4-2)
In the present embodiment, the stator 52 is configured such that the pipe 21 of the casing 2 and the outer peripheral edge of the stator 52 are in point contact, but the balance of the stator 52 needs to be considered. Therefore, in this embodiment, the stator 52 is configured such that the contact points between the inner peripheral surface of the pipe 21 of the casing 2 and the outer peripheral edge of the stator 52 are three points (points P1, P2, and P3). Yes. In other words, there are three places where the stator 52 is supported by the pipe 21. Thereby, the balance of the stator 52 can be maintained.

  In the present embodiment, the notch 56 is formed so as to avoid a contact point between the outer peripheral edge of the stator 52 and the inner peripheral surface of the pipe 21. Thus, by devising the formation position of the notch 56, the core cut space S can be formed so that the balance of the stator 52 is maintained.

(5) Modifications While the embodiment of the present invention has been described with reference to the drawings, the specific configuration is not limited to the above-described embodiment, and can be changed without departing from the gist of the invention. .

(5-1) Modification A
FIG. 6 is a diagram showing a laminated state of the electromagnetic steel sheets 53 for illustrating an example of a method of laminating the electromagnetic steel sheets 53 according to the modified example A (the electromagnetic steel sheets 53 positioned on the lower side in the axial direction are indicated by dotted lines) The electromagnetic steel sheet 53 located on the upper side in the direction is indicated by a solid line).

  In addition to the above embodiment, the lamination method of the electromagnetic steel sheets 53 may be changed. Specifically, the plurality of electromagnetic steel plates 53 may be stacked so that the contact locations (contact points) in the axial direction with the inner peripheral surface of each pipe 21 are shifted. In this case, the electromagnetic steel sheet 53 is rotated and laminated in the circumferential direction so that the tooth portions 55 overlap in the axial direction view.

  As a specific method for laminating the electromagnetic steel plates 53, for example, there is a method of laminating the electromagnetic steel plates 53 one by one in the circumferential direction. In this case, the contact location (contact point) between the outer peripheral edge of the predetermined electromagnetic steel sheet 53 and the inner peripheral surface of the pipe 21 is the outer peripheral edge of the electromagnetic steel sheet 53 adjacent to the electromagnetic steel sheet 53 in the axial direction. It is different from the contact point (contact point) with the peripheral surface.

  Further, for example, the electromagnetic steel sheets 53 may be laminated by rotating in the circumferential direction every predetermined (laminated) several sheets. In this case, the contact location (contact point) between the outer peripheral edge of the electromagnetic steel sheet 53 and the inner peripheral surface of the pipe 21 is different for each number of stacked sheets.

  Note that the rotation angle of the electromagnetic steel sheet 53 may be determined according to the number of the tooth portions 55. For example, when there are six teeth portions 55 as in the above embodiment, as shown in FIG. 6, the electromagnetic steel plates 53 are rotated and laminated so that the rotation angle is 60 °.

  In this modification A, the electromagnetic steel plates 53 are laminated in the stacking direction (axial direction) by stacking the electromagnetic steel plates 53 so that the contact portions with the inner peripheral surfaces of the pipes 21 of the respective electromagnetic steel plates 53 are changed. The position supported by the pipe 21 can be changed. Therefore, the balance of the stator 52 can be improved.

(5-2) Modification B
7 and 8 are views of the pipe 21 and the stator 52 of the casing 2 as viewed from the upper side in the axial direction, for explaining the cross-sectional shape of the stator 52 according to Modification B.

  In the above embodiment, the stator 52 has a cross-sectional shape before the notch 56 is formed, such that the triangular vertices A, B, C have outer peripheral edges connected by the curves C1, C2, C3. However, the present invention is not limited to this, and the cross-sectional shape has an outer peripheral edge connected to the vertices of a polygon other than a triangle (preferably a hexagon). It may be configured to have a shape, or may be elliptical.

  For example, as shown in FIG. 7, the cross-sectional shape before the notch 56 (see FIG. 8) is formed is that the vertices A, B, C, and D shown by the dotted lines in FIG. The stator 52 (the electromagnetic steel plate 53) may be configured to have a shape (see a two-dot chain line portion in FIG. 7) having an outer peripheral edge connected by C2, C3, and C4.

  In this case as well, as in the above embodiment, the curve C1 and the arc portion (not shown) for the string connecting the point A and the apex B of the inner peripheral edge of the pipe 21 do not coincide with each other, and the curve C2 The arc portion (not shown) for the chord connecting the apex B and the apex C on the inner peripheral edge of the pipe 21 does not coincide with the curved line C3 and the chord connecting the apex B and the apex C on the inner peripheral edge of the pipe 21. The arc portion (not shown) with respect to the curve C4 and the arc portion (not shown) with respect to the string connecting the vertex C and vertex D of the inner peripheral edge of the pipe 21 do not coincide.

  And the notch 56 is formed in such a stator 52 from one end surface to the other end surface along the notch line L2, similarly to the said embodiment. In the present modification B, as shown in FIG. 8, it is cut out including contact points P1, P3 between the outer peripheral edge of the stator 52 and the inner peripheral surface of the pipe 21, but in the present invention, From the standpoint of maintaining balance, it is sufficient that there are at least two contact points (contact points) between the outer peripheral edge of the stator 52 and the inner peripheral surface of the pipe 21 (points P2 and P4 in this modification B). ,No problem.

  Further, for example, the stator 52 (electromagnetic steel sheet) may be configured so that the cross-sectional shape before the notch 56 is formed has an elliptical shape. In this case, there are two contact points (contact points) between the outer peripheral edge of the stator 52 and the inner peripheral surface of the pipe 21 before the notch 56 is formed. At this time, the outer periphery of the cross section of the stator 52 does not coincide with the inner periphery of the pipe 21. In addition, when the cross-sectional shape of the stator 52 (the electromagnetic steel plate 53) before the formation of the notch 56 is an elliptical shape, the notch 56 is formed avoiding the contact point (contact point). The shape after the notch 56 is formed approximates the shape as shown in FIG. 8, for example.

  Further, when the cross-sectional shape of the stator 52 (the electromagnetic steel plate 53) before the notch 56 is formed is an elliptical shape, the center of the stator 52 and the center of the pipe 21 (a point on the central axis O) coincide with each other. Will do. Therefore, in such a case, when the electromagnetic steel sheet 53 is rotated and laminated in the circumferential direction as described in Modification A, the center of the substantially circle formed by tying the leading edges of the teeth portion 55 (the stator 52). Is positioned on the central axis O in a state of being fixed to the pipe 21).

  As described above, even if the electromagnetic steel sheet 53 and thus the stator 52 are configured such that the cross-sectional shape before the formation of the notch 56 is a shape other than the shape mentioned in the above embodiment, the casing 2 When resonance vibration occurs, the contact portion (contact point) between the outer peripheral edge of the stator 52 and the inner peripheral surface of the pipe 21 slightly moves near the contact point, and the vibration damping rate increases. Therefore, the same effect as that of the above embodiment can be obtained.

  The present invention is widely applicable to a compressor including a stator that is fixed to the inner peripheral surface of a pipe by shrink fitting.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Casing 21 Pipe 51 Stator 53 Electrical steel plate 56 Notch

JP 2010-288330 A

Claims (4)

A casing (2) containing a cylindrical pipe (21);
A stator (51) that is formed by stacking a plurality of electromagnetic steel plates (53), which are fixed by shrink fitting to the inner peripheral surface of the pipe with a notch (56) formed in the outer peripheral edge;
With
The stator is
The cross-sectional shape before the notch is formed has an outer peripheral edge of a convex simple closed curve different from a circle,
In a state of being fixed to the pipe, in contact with the inner peripheral surface of the pipe at a plurality of locations on the outer peripheral edge,
Compressor (1). The plurality of the electromagnetic steel sheets are laminated so that the contact positions in the axial view with the inner peripheral surface of each of the pipes are shifted,
The compressor according to claim 1. The cross-sectional shape before the notch of the stator is formed is an elliptical shape.
The compressor according to claim 1 or 2. Contact points between the stator and the inner peripheral surface of the pipe are three or more points.
The compressor according to any one of claims 1 to 3.

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