JP7515700B2 - Stators of electric motors, compressors and refrigeration cycle devices - Google Patents

Description

The present disclosure relates to electric motor stators, compressors and refrigeration cycle devices, and in particular to the structure of electric motor stators.

In general, the stator of an electric motor used in a compressor or the like includes a stator core, a coil, and an insulating member that insulates the stator core and the coil. The stator core has a cylindrical back yoke and a plurality of teeth extending from the back yoke toward the central axis. A coil is wound around each tooth via an insulating member, and the coil is disposed in a slot formed between adjacent teeth. In the stator of an electric motor, it is desired to increase the coil space factor (winding density) in order to improve the performance of the electric motor. Therefore, there is a technology that minimizes the dead space of the slot by forming the stator core from a plurality of arc-shaped divided cores, and expands the slot by placing the multiple divided cores in a linearly arranged expanded state during winding, making winding easier (see, for example, Patent Document 1). In Patent Document 1, in the expanded state of the stator core, the back yokes of adjacent divided cores are connected to each other on the outer circumferential side of their circumferential ends, and a V-shaped gap is formed on the inner circumferential side of the connecting portion. When the multiple split cores are deformed into an annular shape after winding, the gap on the inner circumference side of the connecting portion closes. The stator of the electric motor of Patent Document 1 has, as insulating members, a winding frame of the coil end portion formed of an insulating resin material and a slot insulating member. The slot insulating member has a bent portion in a portion (hereinafter referred to as a connecting covering portion) facing the connecting portion of the back yoke to easily obtain insulation between the stator core and the coil. In addition, a film-like insulating material is used as the slot insulating member to ensure a larger winding area. In addition, in the stator of Patent Document 1, in order to prevent the slot insulating member from being pinched between the back yokes of the adjacent split cores when the multiple split cores are deformed into an annular shape, the bent portion is shaped so that the inner side, i.e., the central axis side, becomes a mountain. The bent portion is formed from one end to the other end in the axial direction in the connecting covering portion that covers the connecting portion of the back yoke.

Japanese Patent Application Laid-Open No. 9-191588

As shown in Patent Document 1, when winding the teeth, the winding nozzle passes through the slot between the teeth, above the teeth, and below the teeth. Therefore, in a configuration in which a bent portion is formed from one axial end to the other end of the connecting coating portion, as in the slot insulation member of Patent Document 1, when the winding nozzle changes direction at the end of the tooth during winding, the bent portion of the connecting coating portion may become entangled in the winding. If the slot insulation member becomes entangled in the winding, the arrangement of the winding is disrupted, and the coil space factor (winding density) in the slot decreases.

If the connecting coating part of the slot insulation member were to have a straight shape without any bent parts in order to avoid the slot insulation member becoming wrapped up, there would be no structure to maintain the shape of the connecting coating part when the stator core is in the deployed state, and the shape of the connecting coating part would not be stable. Therefore, even in this case, the slot insulation member could become wrapped up, disrupting the winding arrangement and reducing the space factor of the coil in the slot.

The present disclosure has been made to solve the above-mentioned problems, and aims to provide a stator for an electric motor, a compressor, and a refrigeration cycle device that suppresses a decrease in the coil space factor caused by the disruption of the winding arrangement.

The stator of the electric motor according to the present disclosure comprises a stator core in which a plurality of split cores are connected in an annular shape, the split cores having an arc-shaped back yoke and teeth extending from the circumferential center on the inner surface of the back yoke towards a central axis, coils wound around the teeth of the split core, and an insulating member that insulates the split core and the coils, wherein a slot in which the coils are arranged is formed between two adjacent teeth in the stator core, the insulating member is arranged in the slot and has a continuous film- like slot insulating member covering a surface of an inner wall of the slot in the stator core, the slot insulating member including a connecting covering portion that covers a connecting portion where two of the back yokes are connected to one another on the inner wall of the slot, and the connecting covering portion has a protrusion that protrudes towards the central axis only at a central portion in the axial direction and both end portions on the axial side are planar , or has a protrusion that protrudes radially outward only at both end portions on the axial side and the central portion in the axial direction is planar .
In addition, the compressor according to the present disclosure includes an electric motor having a stator of the above-mentioned electric motor and a rotor rotatably arranged relative to the stator of the electric motor, and a compression element driven by the electric motor to compress a refrigerant.
The refrigeration cycle device according to the present disclosure includes a refrigerant circuit including the above-mentioned compressor, a first heat exchanger, a decompression device, and a second heat exchanger, all of which are connected by refrigerant piping.

According to the present disclosure, the connecting coating portion of the slot insulating member has a protrusion protruding toward the central axis only at the axial center, or has protrusions protruding radially outward only at both axial ends. In either case, the connecting coating portion of the slot insulating member has a stable shape because either of the protrusions is formed. Also, in either case, the connecting coating portion of the slot insulating member has no structure protruding into the slot at both axial ends. Therefore, winding of the slot insulating member during winding is suppressed, and it is possible to provide a stator for an electric motor, a compressor, and a refrigeration cycle device that suppresses a decrease in the space factor of the coil due to a collapse of the winding arrangement.

1 is a perspective view showing a configuration of a stator of an electric motor according to a first embodiment; FIG. 2 is a plan view showing the configuration of the stator shown in FIG. 1 . 2 is a perspective view of a split core in the stator of FIG. 1 as viewed from the inside. FIG. 2 is a perspective view of a split core in the stator of FIG. 1 as viewed from the outside. FIG. 2 is a partial cross-sectional view of the stator of FIG. 1 . 2 is a perspective view of a split stator in the stator of FIG. 1 as viewed from the inside. FIG. FIG. 6 is an explanatory diagram showing a developed state of the stator in FIG. 5 before winding. 2 is a perspective view of adjacent split cores with insulating members attached in the stator of FIG. 1 in an expanded state before winding, as viewed from the inside. FIG. 9 is a perspective view of one of the adjacent split cores 10 in FIG. 8 as viewed from the outside. 2 is a partial configuration diagram of the stator of FIG. 1 in an expanded state before windings are formed, as viewed from the teeth side to the outside. FIG. 11 is a cross-sectional view showing the stator of FIG. 10 along the line AA. 11 is a cross-sectional view showing the stator of FIG. 10 along the line BB. FIG. 7 is a longitudinal sectional view of the split stator of FIG. 6 . 2 is a perspective view showing a positional relationship between the stator and a winding nozzle when the stator of FIG. 1 is wound; FIG. 15 is a partial configuration diagram of the stator and the winding nozzle of FIG. 14 viewed from the lower side of the split stator. FIG. FIG. 2 is a vertical cross-sectional view showing a compressor equipped with the stator shown in FIG. 1 . FIG. 17 is a refrigerant circuit diagram showing a refrigeration cycle device including the compressor shown in FIG. 16. 11 is a partial configuration diagram of a stator according to a second embodiment in an expanded state before windings are seen from the teeth side to the outside. FIG. 19 is a cross-sectional view showing the CC section of the stator in FIG. 18. 19 is a cross-sectional view showing the DD cross section of the stator in FIG. 18.

Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and their description will be omitted or simplified as appropriate. In addition, the shape, size, arrangement, etc. of the configurations shown in each drawing may be changed as appropriate.

Embodiment 1.
(stator)
FIG. 1 is a perspective view showing the configuration of a stator of an electric motor according to the first embodiment. FIG. 2 is a plan view showing the configuration of the stator of FIG. 1. As shown in FIG. 1, the stator 34 has a cylindrical shape. As shown in FIG. 2, the stator 34 is composed of a plurality of split stators 50 arranged in an annular shape in a plan view. As will be described later, the stator 34 constitutes an electric motor 100 together with a rotor that is rotatably provided with respect to the stator 34 (FIG. 16). FIG. 1 shows a central axis O of the stator 34. Hereinafter, the configuration of the stator 34 will be described assuming that the axial direction (direction of the arrow Z) of the central axis O is the up-down direction of the stator 34.

(Split stator 50)
1, nine split stators 50 are connected in an annular shape to form the stator 34. As shown in Fig. 1, the split stator 50 has a split core 10, an insulating member 8 provided on the split core 10, and a coil 5 made of a conductive wire wound around the split core 10.

(Split core 10)
Fig. 3 is a perspective view of the split core in the stator of Fig. 1 as seen from the inside. Fig. 4 is a perspective view of the split core in the stator of Fig. 1 as seen from the outside. As shown in Fig. 3, the split core 10 has a plurality of core pieces 1. The core pieces 1 are made of a plate-like member having magnetism, and are formed, for example, by punching out an electromagnetic steel sheet, which is a soft magnetic material, with a die. The plurality of core pieces 1 are stacked in the vertical direction (arrow Z direction) and integrated by crimping or the like to form a block-shaped split core 10 having a thickness in the vertical direction (arrow Z direction). In the following description, the plurality of split cores 10 in the stator 34 may be collectively referred to as a stator core.

The split core 10 has an arc-shaped back yoke 10a that constitutes the outer periphery of the stator 34, teeth 10b extending from the inner surface 10ai of the back yoke 10a toward the central axis O (FIG. 1), and shoes 10c provided on both circumferential sides of the tip end 10b1 of the teeth 10b. As shown in FIG. 4, the back yoke 10a has an outer circumferential surface 10ao that is arc-shaped in a plan view, and as shown in FIG. 3, an inner surface 10ai that is linear in a plan view, and two side surfaces 10as that connect the outer circumferential surface 10ao (FIG. 4) and the inner surface 10ai at both ends in the circumferential direction. The split core 10 is connected to the adjacent split core 10 at both ends in the circumferential direction of the back yoke 10a.

Figure 5 is a partial cross-sectional view of the stator 34 in Figure 1. As shown in Figure 5, the outer peripheral surfaces 10ao of the side surfaces 10as of the back yokes 10a of adjacent split cores 50 are connected. Hereinafter, the portions of the back yokes 10a of adjacent split cores 10 that are connected to each other may be referred to as connection portions.

The teeth 10b extend from the circumferential center of the inner surface 10ai of the back yoke 10a toward the central axis O. In the example shown in FIG. 3, the teeth 10b have a constant thickness in the circumferential direction on the back yoke 10a side and the central axis O (FIG. 1) side, and the inner surface 10ai of the back yoke 10a and the side surface 10bs of the teeth 10b are connected at right angles. In this embodiment, the inner surface 10ai of the back yoke 10a and the side surface 10bs of the teeth 10b are connected at right angles, but they do not have to be at right angles.

As shown in Figure 3, the shoe 10c has an inner surface 10ci on the central axis O side and an outer surface 10co (Figure 4) on the back yoke 10a side, and has a tapered shape. The inner surface 10ci of the shoe 10c and the inner surface 10bi of the teeth 10b are smoothly connected to form the inner surface 10i of the split core 10. The inner surface 10i of the split core 10 has an arc shape.

When multiple split stators 50 are arranged in a ring shape as shown in Fig. 2, the two side surfaces 10as of the back yoke 10a of the split core 10 shown in Fig. 4 come into contact with the side surfaces 10as of the back yoke 10a of the other two adjacent split cores 10. Hereinafter, the state in which multiple split stators 50 are arranged in a ring shape may be referred to as the stator core being in a closed state.

As shown in Figure 2, a slot 6 is formed between adjacent split cores 10 in the stator 34, and a coil 5 wound around the tooth 10b (Figure 4) is arranged in the slot 6 via an insulating member 8. That is, the slot 6 is a space surrounded by the side surfaces 10bs of the teeth 10b facing each other in adjacent split cores 10, the outer surfaces 10co of the shoes 10c facing each other, and the inner surfaces 10ai of the adjacent back yokes 10a. Hereinafter, these surfaces that form the slot 6 in adjacent split cores 10 may be referred to as the slot inner walls.

(Coil 5)
FIG. 6 is a perspective view of the split stator 50 of the stator of FIG. 1 from the inside. As shown in FIG. 6, the coil 5 is a conductor composed of a core wire, which is a conductor, and an insulating coating covering the core wire. The core wire is made of, for example, copper, aluminum, or a conductive alloy. The conductor constituting the coil 5 is wound multiple times around the teeth 10b of the split core 10 via an insulating member 8, and the coil 5 has a long ring shape in the vertical direction (arrow Z direction). The coil 5 forms a magnetic pole by winding the conductor wire around the teeth 10b. Therefore, when a current flows through the conductor wire of the coil, a magnetic flux is generated for each tooth 10b. The winding wound multiple times around the teeth 10b (FIG. 3) between the back yoke 10a and the shoe 10c is provided in multiple layers at the upper end of the split stator 50, and each layer includes multiple windings arranged in a row.

(Insulating member 8)
Fig. 7 is an explanatory diagram showing the unfolded state of the stator 34 in Fig. 5 before winding. As shown in Fig. 7, in the manufacturing stage of the stator 34, winding is performed in a state in which the multiple split cores 10 are arranged in a straight line. Hereinafter, the state in which the multiple split cores 10 are arranged in a straight line may be referred to as the unfolded state. In the unfolded state, a V-shaped gap 10g is formed on the inner surface 10ai side of the side surface 10as of the back yoke 10a between adjacent split cores 10 connected by the connecting portion 10r.

Figure 8 is an oblique view from the inside of adjacent split cores 10 in the stator of Figure 1, with insulating members 8 attached, in an expanded state before winding. Figure 9 is an oblique view from the outside of one of the adjacent split cores 10 in Figure 8. As shown in Figure 8, the insulating member 8 insulates the split core 10 made of iron or the like from the coil 5 made of copper or the like. The insulating member 8 has a set of end surface insulating members 4 attached to both end surfaces of the split core 10 in the axial direction (arrow Z direction), and a continuous slot insulating member 7 arranged in the slot 6 of the stator core and covering the surface of the slot inner wall.

Figure 10 is a partial configuration diagram of the stator in Figure 1 in an expanded state before winding, viewed from the teeth side to the outside. Figure 11 is a cross-sectional view showing the A-A section of the stator in Figure 10. Figure 12 is a cross-sectional view showing the B-B section of the stator in Figure 10. Below, the configuration of the slot insulating member 7 and the set of end face insulating members 4 will be explained with reference to Figures 7 to 12.

(Slot insulating member 7)
7, a slot insulating member 7 is provided in each slot 6 of the stator 34. The slot insulating member 7 ensures an insulating distance, equivalent to its thickness, between the coil 5 and the inner peripheral wall of the slot of an adjacent split core 10, thereby insulating them from each other.

As shown in Figure 8, the slot insulation member 7 arranged in each slot 6 is composed of a sheet of film-like insulating material. The slot insulation member 7 can be composed of, for example, a PET (polyethylene terephthalate) film.

7, the slot insulating member 7 seamlessly covers the slot inner walls of adjacent split cores 10 that form the slot 6, and the connecting portions 10r of adjacent split cores 10 are also covered by the slot insulating member 7. The slot insulating member 7 includes a back yoke covering portion 7a that covers adjacent back yokes 10a of the slot inner walls, two tooth covering portions 7b that cover two teeth 10b, and two shoe covering portions 7c that cover two shoes 10c. Hereinafter, the circumferential center region of the back yoke covering portion 7a that covers the connecting portions 10r of adjacent back yokes 10a may be referred to as the connecting covering portion 70 (see FIG. 10).

8, in the deployed state in which adjacent back yokes 10a are arranged in a straight line, the upper end 7a1 and the lower end 7a2 of the back yoke covering portion 7a are arranged along the inner surface 10ai of the back yoke 10a by a set of end surface insulating members 4. However, the set of end surface insulating members 4 does not have a structure for directly holding the connecting covering portion 70 of the slot insulating member 7.

As shown in FIG. 12, the connecting covering portion 70 that covers the connecting portion 10r in the back yoke covering portion 7a of the slot insulating member 7 has a protruding portion 71 that extends in the axial direction (arrow Z direction) and has a peak on the central axis O side. As shown in FIG. 10, the connecting covering portion 70 of each slot insulating member 7 has a protruding portion 71 having a certain length in the axial direction (arrow Z direction). The protruding portion 71 with a peak on the central axis O side is formed only in the central portion 70c in the axial direction (arrow Z direction) of the connecting covering portion 70 of the back yoke covering portion 7a, and is not formed in the upper end portion 70a and the lower end portion 70b of the connecting covering portion 70. As shown in FIG. 11, in the expanded state of the stator core, the upper end portion 70a and the lower end portion 70b of the connecting covering portion 70, i.e., the ends on both sides of the axial direction (arrow Z direction) of the connecting covering portion 70, have an approximately planar shape that follows the inner surface 10ai of the back yoke 10a.

In this way, the shape of the connecting covering part 70 is stable because the protruding part 71 is formed at the axial center part 70c of the connecting covering part 70, and the end part of the connecting covering part 70 does not have a structure that protrudes into the slot 6. Therefore, the winding of the slot insulating member during winding is suppressed, and the arrangement of the winding is prevented from being distorted.

In the example shown in Fig. 11, the ends of the connecting cover 70 on both axial sides are generally planar, but the ends of the connecting cover 70 may have a different protrusion with a peak on the radially outer side. When the stator core is closed as shown in Fig. 1, the pair of end surface insulating members 4 of adjacent split stators 50 are spaced apart from each other on the outer periphery side of the back yoke cover 7a. Therefore, even if the ends of the connecting cover 70 have a different protrusion with a peak on the radially outer side, the deformation of the stator core is not hindered when the stator core is deformed into an annular shape after winding.

(A set of end surface insulating members 4)
As shown in Fig. 8, a set of end surface insulating members 4 is provided for each split core 10. The set of end surface insulating members 4 is composed of an upper end surface insulating member 2 attached to the upper end surface of the split core 10 and a lower end surface insulating member 3 attached to the lower end surface of the split core 10. The upper end surface insulating member 2 ensures an insulation distance of its thickness between the coil 5 and the upper end surface of the split core 10, thereby insulating them from each other. The lower end surface insulating member 3 ensures an insulation distance of its thickness between the coil 5 and the lower end surface of the split core 10, thereby insulating them from each other. The set of end surface insulating members 4 attached to the split core 10 also functions as a winding frame for the coil 5.

(Upper end surface insulating member 2)
The upper end surface insulating member 2 has an outer flange 2a, an inner flange 2b provided radially inward from the outer flange 2a, and a teeth end surface covering portion 2c provided between the outer flange 2a and the inner flange 2b. The upper end surface insulating member 2 also has a step portion 2d connecting the teeth end surface covering portion 2c and the outer flange 2a, and a slope portion 2e (FIG. 9) connecting the teeth end surface covering portion 2c and the inner flange 2b. The outer flange 2a and the inner flange 2b regulate the arrangement of the upper layer windings among the multiple layers of windings that constitute the coil 5. The step portion 2d and the slope portion 2e (FIG. 9) regulate the arrangement of the lower layer windings among the multiple layers of windings that constitute the coil 5.

The outer flange 2a has a rectangular parallelepiped shape, and the lower surface of the outer flange 2a is in contact with the central axis O side of the upper surface of the back yoke 10a. The outer flange 2a is arranged on the back yoke 10a so that the inner surface of the outer flange 2a is flush with the inner surface 10ai (FIG. 3) of the back yoke 10a. A part of the back yoke covering portion 7a of the slot insulating member 7, specifically the upper end portion 7a1 of the back yoke covering portion 7a, is arranged so as to be aligned with the lower part on both circumferential sides of the inner surface of the outer flange 2a. The circumferential width of the outer flange 2a is shorter than the circumferential width of the back yoke 10a, and the outer flanges 2a of adjacent split stators 50 are spaced apart.

The inner flange 2b has an approximately rectangular parallelepiped shape with the inner surface 2bi on the central axis O side being arc-shaped. The inner surface 2bi of the inner flange 2b is formed in an arc shape with approximately the same curvature as the inner surface 10i of the split core 10, and the inner flange 2b is arranged on the shoe 10c so that the inner surface 2bi of the inner flange 2b and the inner surface 10i of the split core 10 are flush with each other. Slits 2b1 are formed in the lower parts of both circumferential sides of the inner flange 2b. Each slit 2b1 is formed from the inclined surface 2e to the side surface of the inner flange 2b in the circumferential direction, and both circumferential sides of each slit 2b1 are open. A part of the shoe covering portion 7c of the slot insulating member 7 is arranged in the slit 2b1. Specifically, the upper end of the shoe covering portion 7c is inserted into the slit 2b1 from below, and the position of the upper end of the shoe covering portion 7c is regulated.

The tooth end surface covering portion 2c is connected to the lower portion of the outer flange 2a and the lower portion of the inner flange 2b. The tooth end surface covering portion 2c is formed, for example, from a plate-shaped member bent into a U-shape, and the ends 2c1 on both circumferential sides of the tooth end surface covering portion 2c extend downward. The tooth end surface covering portion 2c covers the top surface of the tooth 10b and the upper ends of the two side surfaces 10bs (Figure 4) of the tooth 10b.

The step 2d is configured so that the step becomes higher as it moves from the tooth end surface covering portion 2c toward the outer flange 2a. In other words, the outer diameter of the step 2d increases toward the outer flange 2a. The step 2d has a roughly U-shape that fits along the tooth end surface covering portion 2c, and the ends 2d1 on both circumferential sides of the step 2d extend downward.

A gap is formed between the end 2d1 of the step 2d and the inner surface of the outer flange 2a, and the tooth covering portion 7b side at the upper end 7a1 of the back yoke covering portion 7a is placed in this gap and pressed against the back yoke 10a side of the split core 10. A gap is also formed between the end 2d1 of the step 2d and the end 2c1 of the tooth end face covering portion 2c, and the back yoke covering portion 7a side at the upper end of the tooth covering portion 7b is placed in this gap and pressed against the tooth 10b side of the split core 10. In other words, the end 2d1 of the step 2d presses the boundary between the tooth covering portion 7b and the back yoke covering portion 7a in the slot insulating member 7 against the split core 10. Hereinafter, the end 2d1 of the step 2d may be referred to as the pressing portion.

As shown in Figure 9, the sloped surface 2e has an inclined shape such that the outer diameter increases from the tooth end surface covering portion 2c toward the inner flange 2b. The sloped surface 2e has a generally U-shape along the tooth end surface covering portion 2c, and the ends 2e1 on both circumferential sides of the sloped surface 2e extend downward. However, in the example shown in Figure 9, the ends 2e1 extending downward in the sloped surface 2e are not provided at the height position where the slit 2b1 is formed so as not to impede the insertion of the shoe covering portion 7c into the slit 2b1 formed in the lower part of the inner flange 2b.

(Lower end surface insulating member 3)
8, the bottom end surface insulating member 3 has almost the same configuration as the top end surface insulating member 2 when it is vertically symmetrical, and has an outer flange 3a, an inner flange 3b, a teeth end surface covering portion 3c, a step portion (not shown), and a slope portion 3e (FIG. 9) like the top end surface insulating member 2. A slit 3b1 is formed in the inner flange 3b of the bottom end surface insulating member 3. However, unlike the outer flange 2a of the top end surface insulating member 2, a wiring groove 3f is formed in the outer flange 3a of the bottom end surface insulating member 3. The end portion of the conductor that constitutes the coil 5 is disposed in the wiring groove 3f.

Figure 13 is a cross-sectional view of the split stator 50 of Figure 6. In Figure 13, the winding order of the multiple windings that make up the coil 5 is indicated. Figure 14 is a perspective view showing the positional relationship between the stator 34 and the winding nozzle 20 when winding the stator 34 of Figure 1. Figure 15 is a partial configuration diagram of the stator 34 and the winding nozzle 20 of Figure 14 viewed from the underside of the split stator 50. The winding process during the manufacture of the stator 34 will be described with reference to Figures 13 to 15.

As shown in FIG. 14, the winding process is performed with the slot insulating member 7 attached to the inner peripheral wall of each slot and with a set of end surface insulating members 4 attached to both axial end surfaces of each divided core 10. In the winding process, the coils 5 are wound with the divided cores 10 linearly deployed. Specifically, when the winding process is performed, the divided cores 10 with the insulating member 8 attached are held by a jig 21 or the like so that their back yokes 10a are arranged linearly. A plurality of winding nozzles 20 are provided at regular intervals, and the coils 5 are wound on each of the teeth 10b with the divided cores 10 held by the jig 21. The winding nozzles 20 move relative to the jig 21 while maintaining a certain interval, so that the conductor wire 5a from each winding nozzle 20 is wound on the tooth 10b corresponding to the winding nozzle 20. At this time, the winding nozzles 20 pass through the slots 6 on both sides of the corresponding divided core 10, above and below.

In the example shown in FIG. 13, the winding starts from the step 2d side of the upper end surface insulating member 2 on the upper end surface of the divided core 10. The first winding is made at a position where it contacts the inner surface of the first step of the step 2d of the upper end surface insulating member 2, and the first layer of conductor is sequentially wound in the direction of arrow D1 from the step 2d side toward the inner flange 2b in the tooth end surface covering portion 2c. After a fixed number of windings are made for the first layer, the second layer of conductor is sequentially wound in the direction of arrow D2 toward the outer flange 2a. The second layer of conductor is wound in a bale-stacked position relationship so as to contact the adjacent conductor in the first layer. Thereafter, the third layer and subsequent layers are similarly wound so as to be in a bale-stacked position relationship with the conductor in the layer immediately below. When a predetermined number of windings are completed, the end of the conductor 5a is placed in the wiring groove 3f formed in the outer flange 3a of the lower end surface insulating member 3.

In the coil 5, the windings of the lower layers, for example the first and second layers, are arranged between the step 2d and the slope 2e in the upper end surface insulating member 2, and the radial position is regulated by the step 2d and the slope 2e. Specifically, the winding closest to the outer flange 2a in each layer of the lower layer contacts the inner surface of the step 2d, and the winding closest to the inner flange 2b in each layer of the lower layer contacts the slope 2e. The winding closest to the outer flange 2a of the first layer contacts the inner surface of the first step of the step 2d, and the winding closest to the outer flange 2a of the second layer contacts the inner surface of the second step formed in the step 2d, which is higher than the first step and is closer to the outer flange 2a. With this configuration, the windings in the lower layer of the coil 5 are prevented from becoming separated radially, and the windings in the lower layer of the coil 5 and the windings in the upper layers (e.g., the third layer or higher) can be aligned and arranged.

As shown in Figure 15, the stator 34 is composed of multiple split stators 50, each split into teeth 10b, so that when deployed during winding, the width between the teeth 10b is wider than when the stator core is closed. This makes it possible to wind a thicker conductor by expanding the width of the winding nozzle 20.

As described above, the connecting cover 70 of the slot insulating member 7 has no structure protruding into the slot 6 at both axial ends of the connecting cover 70, and the shape is stabilized by the protruding portion 71. This prevents the slot insulating member 7 from being wound during winding, ensuring the alignment of the winding.

15, the back yoke covering portion 7a of the slot insulating member 7 is shaped to conform to the inner surface 10ai of the back yoke 10a during winding. Therefore, the connecting covering portion 70 is positioned radially outward of the orbit of the conductor 5a during winding, which further suppresses winding of the slot insulating member 7 during winding.

As described above, the stator 34 of the electric motor of the first embodiment includes a stator core composed of a plurality of split cores 10 connected in an annular shape, a coil 5, and an insulating member 8 that insulates the split cores 10 and the coil 5. Each split core 10 has an arc-shaped back yoke 10a and teeth 10b extending from the circumferential center of the inner surface 10ai of the back yoke 10a toward the central axis O, and the coil 5 is wound around the teeth 10b of each split core 10. A slot 6 in which the coil 5 is disposed is formed between two adjacent teeth 10b in the stator core. The insulating member 8 has a continuous slot insulating member 7 that covers the surface of the slot inner wall in the stator core. The slot insulating member 7 includes a connecting covering portion 70 that covers the connecting portion 10r where two back yokes 10a are connected among the inner walls of the slot, and the connecting covering portion 70 has a protruding portion 71 that protrudes toward the central axis O only at the central portion 70c in the axial direction (arrow Z direction).

As a result, the shape of the connecting coating part 70 of the slot insulating member 7 is stabilized by the protrusion 71 provided at the center part 70c in the axial direction (arrow Z direction), and there is no protruding structure at either end in the axial direction. Therefore, when the winding nozzle 20 changes direction at the end of the tooth 10b during winding, winding of the connecting coating part 70 of the slot insulating member 7 is suppressed, and the alignment of the windings can be ensured. This makes it possible to provide a stator 34 for an electric motor in which a decrease in the space factor of the coil 5 due to the collapse of the winding arrangement is suppressed.

In addition, the insulating member 8 has a pair of end surface insulating members 4 attached to both end surfaces of the split core 10 in the axial direction (arrow Z direction). This makes it possible to regulate the upper and lower positions of the slot insulating members 7 while insulating the upper and lower end surfaces of the split core 10 from the coil 5.

The stator core also has shoes 10c protruding from both circumferential ends of the tip portions 10b1 of the teeth 10b. The slot insulating member 7 includes a shoe covering portion 7c that covers the shoe 10c on the inner peripheral wall of the slot. The set of end face insulating members 4 has slits (slits 2b1 and slits 3b1) that secure both axial ends of the shoe covering portion 7c.

This allows the shoe covering portion 7c of the slot insulating member 7 to be aligned with the shoe 10c of the split core 10 to prevent slack, and prevents the shoe covering portion 7c from being rolled up during winding. This makes it possible to more reliably prevent the windings from becoming misaligned.

The slot insulating member 7 includes a back yoke covering portion 7a that covers the back yoke 10a of the slot inner wall, and a tooth covering portion 7b that covers the teeth 10b of the slot inner wall. One end face insulating member (upper end face insulating member 2) of the set of end face insulating members 4 has a pressing portion (end portion 2d1 of step portion 2d) that presses the boundary portion between the tooth covering portion 7b and the back yoke covering portion 7a in the slot insulating member 7 toward the split core 10.

This allows the shape of the slot insulating member 7 to be maintained so that the tooth covering portion 7b and the back yoke covering portion 7a are aligned with the split core 10, and prevents the tooth covering portion 7b and the back yoke covering portion 7a from becoming entangled during winding. This makes it possible to more reliably prevent the windings from becoming misaligned.

<Rotary Compressor>
Fig. 16 is a vertical cross-sectional view showing a compressor equipped with the stator of Fig. 1. A rotary compressor 300 to which the above-mentioned stator 34 is applied will be described below with reference to Fig. 16. The rotary compressor 300 is used, for example, in an air-conditioning device, and includes a sealed container 307, a compression element 301 arranged in the sealed container 307, and an electric motor 100 that drives the compression element 301. The electric motor 100 is composed of the above-mentioned stator 34, a rotor 33 provided rotatably relative to the stator 34, and the like.

The compression element 301 compresses the refrigerant. The compression element 301 has a cylinder 302 having a cylinder chamber 303, a shaft 37 rotated by the electric motor 100, and a rolling piston 304 fitted to the shaft 37. The compression element 301 also has a vane (not shown) that divides the inside of the cylinder chamber 303 into a refrigerant intake side and a refrigerant compression side, and an upper frame 305 and a lower frame 306 into which the shaft 37 is inserted and which close the axial end face of the cylinder chamber 303. An upper discharge muffler 308 is attached to the upper frame 305, and a lower discharge muffler 309 is attached to the lower frame 306. The refrigerant is discharged into the internal space of the sealed container 307 through the upper discharge muffler 308 and the lower discharge muffler 309.

The sealed container 307 is a cylindrical container having a lid and a bottom. A glass terminal 311 is fixed to the lid of the sealed container 307. Refrigeration oil (not shown) for lubricating each sliding part of the compression element 301 is stored in the bottom of the sealed container 307. The shaft 37 is rotatably held by an upper frame 305 and a lower frame 306 which serve as bearings. The rolling piston 304 rotates eccentrically within a cylinder chamber 303 inside the cylinder 302. The shaft 37 has an eccentric shaft part into which the rolling piston 304 is fitted.

The stator 34 of the electric motor 100 is incorporated into the sealed container 307 by shrink fitting, press fitting, welding, or the like, and is fixed to the inner peripheral surface of the sealed container 307. Electric power is supplied to the coil 5 of the stator 34 via glass terminals 311. The rotor 33 of the electric motor 100 has a permanent magnet 35 and a rotor core 36, and an axial hole is formed in the center of the rotor core 36. The shaft 37 is fixed to the axial hole of the rotor 33. In the electric motor 100, the rotor is disposed inside the stator 34, and the shaft 37 is inserted into the axial hole of the rotor 33 so as to be aligned with the central axis O (FIG. 1) of the stator 34.

In addition, an accumulator 310 that stores refrigerant gas is attached to the outside of the sealed container 307. A suction pipe 313 that connects to the accumulator 310 is fixed to the sealed container 307, and refrigerant gas is supplied from the accumulator 310 to the cylinder 302 in the sealed container 307 via the suction pipe 313. In addition, a discharge pipe 312 that discharges the refrigerant to the outside is provided on the lid of the sealed container 307.

Next, the operation of the rotary compressor 300 will be described. The refrigerant gas supplied from the accumulator 310 is supplied through the suction pipe 313 into the cylinder chamber 303 of the cylinder 302. When the rotor 33 rotates as a result of the motor 100 being driven by the inverter (not shown), the shaft 37 rotates along with the rotor 33. Then, the rolling piston 304 fitted to the shaft 37 rotates eccentrically in the cylinder chamber 303, and the refrigerant is compressed in the cylinder chamber 303. The refrigerant compressed in the cylinder chamber 303 passes through the upper discharge muffler 308 or the lower discharge muffler 309, and further passes through the air holes (not shown) of the rotor core 36, etc., and rises in the sealed container 307. The refrigerant that has risen in the sealed container 307 is discharged from the discharge pipe 312.

In the electric motor 100 having the stator 34 described above, the multiple split cores 10 are deployed in a linear arrangement during winding. Therefore, during winding, the width of the slot 6 formed between the teeth 10b is expanded more than the width of the slot 6 when the multiple split cores 10 are closed in a ring shape, so the width of the winding nozzle 20 can be expanded and thick wire can be wound. This improves the motor efficiency of the electric motor 100 and increases the output. Therefore, by applying the electric motor 100 to the rotary compressor 300, the operating efficiency of the rotary compressor 300 can be improved and the output can be increased.

In addition, the electric motor 100 having the stator 34 is not limited to the rotary compressor 300 described above and can be applied to other types of compressors.

<Refrigeration cycle device>
Fig. 17 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 400 including the compressor of Fig. 16. Hereinafter, the refrigeration cycle apparatus 400 including the above-mentioned rotary compressor 300 will be described with reference to Fig. 17. Hereinafter, the configuration of the refrigeration cycle apparatus 400 will be described assuming that the refrigeration cycle apparatus 400 is an air-conditioning apparatus.

17, the refrigeration cycle device 400 includes a refrigerant circuit including the rotary compressor 300 described above, and a control unit 406 that controls the operation of the refrigeration cycle device 400. The refrigerant circuit is formed by connecting the rotary compressor 300, the four-way valve 401, the first heat exchanger 402, the pressure reducing device 403, and the second heat exchanger 404 with the refrigerant piping 405. The second heat exchanger 404 is installed, for example, inside a room that is a space to be air-conditioned, and the first heat exchanger 402 is installed, for example, outside the room. The control unit 406 is composed of, for example, a microcomputer, and controls the operation of the four-way valve 401 and the rotary compressor 300. The four-way valve 401 switches the flow direction of the refrigerant.

Next, the operation of the refrigeration cycle device 400 will be described. The rotary compressor 300 compresses the refrigerant that is sucked in and sends it out as a high-temperature, high-pressure gas refrigerant. In the first connection state shown by the solid line in FIG. 17, the four-way valve 401 flows the refrigerant sent out from the rotary compressor 300 to the first heat exchanger 402. When the four-way valve 401 is in the first connection state, the first heat exchanger 402 functions as a condenser. The first heat exchanger 402 exchanges heat between the refrigerant sent out from the rotary compressor 300 and air (e.g., outdoor air) and sends it out. In the first heat exchanger 402, the refrigerant condenses and liquefies by releasing heat to the air. The pressure reducing device 403 expands the liquid refrigerant sent out from the first heat exchanger 402 and sends it out as a low-temperature, low-pressure liquid refrigerant. When the four-way valve 401 is in the first connection state, the second heat exchanger 404 functions as an evaporator. The second heat exchanger 404 exchanges heat between the low-temperature, low-pressure liquid refrigerant sent from the pressure reducing device 403 and air (for example, air in the space to be air-conditioned) and sends it out. In the second heat exchanger 404, the refrigerant is sucked from the air and evaporates. At this time, the air that has exchanged heat with the refrigerant in the second heat exchanger 404 is cooled. The cooled air is supplied to the space to be air-conditioned (for example, inside a room) by a blower (not shown), and the space to be air-conditioned is cooled. The gas refrigerant sent out from the second heat exchanger 404 is sent to the rotary compressor 300 via the four-way valve 401, and is compressed again in the rotary compressor 300. Thereafter, the same cycle is repeated.

When the four-way valve 401 is in the second connection state shown by the dashed line in Fig. 17, the refrigerant sent out from the rotary compressor 300 is sent to the second heat exchanger 404, which functions as a condenser, and the first heat exchanger 402 functions as an evaporator. As a result, when the four-way valve 401 is in the second connection state, heating is performed in the space to be air-conditioned.

As described above, the compressor (rotary compressor 300) according to the present disclosure includes an electric motor 100 having a stator 34 and a rotor 33 rotatably arranged relative to the stator 34, and a compression element 301 that is driven by the electric motor 100 and compresses the refrigerant. This makes it possible to improve the operating efficiency and increase the output of the compressor (rotary compressor 300).

The refrigeration cycle device 400 according to the present disclosure is provided with a refrigerant circuit including a compressor (rotary compressor 300), a first heat exchanger 402, a pressure reducing device 403, and a second heat exchanger 404, all connected by refrigerant piping 405. As a result, the refrigeration cycle device 400 is provided with a rotary compressor 300 with increased output, thereby improving operating efficiency and energy efficiency.

The refrigeration cycle device 400 equipped with the rotary compressor 300 is not limited to the air conditioning device described above. The refrigerant circuit of the refrigeration cycle device 400 is not limited to the refrigerant circuit described above and can be modified as appropriate. For example, the four-way valve 401 can be omitted in the refrigeration cycle device 400.

Embodiment 2.
Fig. 18 is a partial configuration diagram of a stator according to embodiment 2 in an expanded state before winding, viewed from the teeth side to the outside. Fig. 19 is a cross-sectional view showing a CC cross section of the stator in Fig. 18. Fig. 20 is a cross-sectional view showing a D-D cross section of the stator in Fig. 18. In the stator 34 of embodiment 2, the configuration of the connecting covering portion 70 in the back yoke covering portion 7a of the slot insulating member 7 differs from that of the stator 34 of embodiment 1. Below, the points in the stator 34 of embodiment 2 that are different from that of embodiment 1 will be described with reference to Figs. 18 to 20.

In the above-mentioned first embodiment, as shown in Figures 10 to 12, a protrusion 71 that protrudes toward the shaft side is formed in the axial center 70c of the connecting covering part 70 of the slot insulating member 7, and no protrusion 71 is formed on either axial end of the connecting covering part 70. As shown in Figure 18, in the stator 34 of the second embodiment, as in the first embodiment, a protrusion 72 is formed in the connecting covering part 70 in the back yoke covering part 7a of the slot insulating member 7. However, in the stator of the second embodiment, the protruding direction of the protrusion 72 provided in the axial center 70c and the position at which the protrusion 72 is provided are different from those in the first embodiment.

As shown in FIG. 19, the connecting covering portion 70 that covers the connecting portion 10r in the back yoke covering portion 7a of the slot insulating member 7 has a protruding portion 72 that extends in the axial direction (arrow Z direction) and becomes a mountain on the radially outer side. As shown in FIG. 18, the connecting covering portion 70 of each slot insulating member 7 has two protruding portions 72 having a certain length in the axial direction (arrow Z direction). The protruding portions 72 that become a mountain on the radially outer side are formed only on the upper end portion 70a and the lower end portion 70b of the connecting covering portion 70 of the back yoke covering portion 7a, and are not formed on the central portion 70c in the axial direction (arrow Z direction) of the connecting covering portion 70. As shown in FIG. 20, in the deployed state, the central portion 70c in the axial direction (arrow Z direction) of the connecting covering portion 70 has an approximately planar shape that follows the inner surface 10ai of the back yoke 10a.

As described above, the stator 34 of the electric motor of the second embodiment includes a stator core composed of a plurality of split cores 10 connected in an annular shape, a coil 5, and an insulating member 8 that insulates the split cores 10 and the coil 5. Each split core 10 has an arc-shaped back yoke 10a and teeth 10b extending from the circumferential center of the inner surface 10ai of the back yoke 10a toward the central axis O, and the coil 5 is wound around the teeth 10b of each split core 10. A slot 6 in which the coil 5 is disposed is formed between two adjacent teeth 10b in the stator core. The insulating member 8 has a continuous slot insulating member 7 that covers the surface of the inner wall of the slot in the stator core. The slot insulating member 7 includes a connecting covering portion 70 that covers the connecting portion 10r where two back yokes 10a are connected among the inner walls of the slot, and the connecting covering portion 70 has protrusions 72 that protrude radially outward only at both ends in the axial direction (arrow Z direction).

As a result, the shape of the connecting covering portion 70 of the slot insulating member 7 is stabilized by the protruding portions 72 that protrude radially outward and are provided at both ends in the axial direction (arrow Z direction), and the ends on both axial sides and the central portion 70c do not have a structure that protrudes into the slot 6. Therefore, in the second embodiment as well, as in the first embodiment, when the winding nozzle 20 changes direction at the end of the tooth 10b during winding, winding of the connecting covering portion 70 of the slot insulating member 7 is suppressed, and the alignment of the windings can be ensured. Therefore, it is possible to provide a stator 34 for an electric motor in which a decrease in the space factor of the coil 5 due to the collapse of the winding arrangement is suppressed.

The stator 34 of the second embodiment can be applied to the rotary compressor 300, as in the first embodiment, and in this case, the operating efficiency of the rotary compressor 300 can be improved and the output can be increased. Also, as in the first embodiment, the compressor (rotary compressor 300) to which the stator 34 of the second embodiment is applied can be applied to the refrigeration cycle device 400. In this case, the energy efficiency of the refrigeration cycle device 400 can be improved.

Note that each embodiment may be modified or omitted as appropriate. For example, in the first and second embodiments, the stator 34 is described as being composed of nine split stators, but the number of split stators constituting the stator 34 is not limited to this.

1 Core piece, 2 Upper end surface insulating member, 2a Outer flange, 2b Inner flange, 2b1 Slit, 2bi Inner surface, 2c Teeth end surface covering portion, 2c1 End, 2d Step portion, 2d1 End, 2e Slope portion, 2e1 End, 3 Lower end surface insulating member, 3a Outer flange, 3b Inner flange, 3b1 Slit, 3c Teeth end surface covering portion, 3e Slope portion, 3f Wiring groove, 4 End surface insulating member, 5 Coil, 5a Conductor, 6 Slot, 7 Slot insulating member, 7a Back yoke covering portion, 7b Teeth covering portion, 7c Shoe covering portion, 8 Insulating member, 10 Split core, 10a Back yoke, 10b Teeth, 10c Shoe, 10g Gap, 10i Inner surface, 10r Connecting portion, 20 Winding nozzle, 21 jig, 33 rotor, 34 stator, 35 permanent magnet, 36 rotor core, 37 shaft, 50 split stator, 70 connecting covering portion, 71 protruding portion, 72 protruding portion, 100 electric motor, 300 rotary compressor, 301 compression element, 302 cylinder, 303 cylinder chamber, 304 rolling piston, 305 upper frame, 306 lower frame, 307 sealed container, 308 upper discharge muffler, 309 lower discharge muffler, 310 accumulator, 311 glass terminal, 312 discharge pipe, 313 suction pipe, 400 refrigeration cycle device, 401 four-way valve, 402 first heat exchanger, 403 pressure reducing device, 404 second heat exchanger, 405 refrigerant piping, 406 control portion, O central axis.

Claims (6)

a stator core including a plurality of split cores connected in an annular shape, the split cores each having an arc-shaped back yoke and teeth extending from a circumferential center on an inner surface of the back yoke toward a central axis;
A coil is wound around the teeth of the split core;
an insulating member that insulates the split core from the coil,
A slot in which the coil is disposed is formed between two adjacent teeth in the stator core,
The insulating member is
a slot insulating member in the form of a continuous film disposed in the slot and covering a surface of an inner peripheral wall of the slot in the stator core;
the slot insulating member includes a connecting covering portion that covers a connecting portion of the slot inner wall where the two back yokes are connected,
The connecting covering portion has a protruding portion protruding toward the central axis only at a central portion in the axial direction and both end portions in the axial direction are planar , or has a protruding portion protruding radially outward only at both end portions in the axial direction and has a central portion in the axial direction.
Stator of an electric motor. The insulating member is
2. The stator of claim 1, further comprising a pair of end surface insulating members attached to both end surfaces of the split core in the axial direction. the stator core has shoes protruding from both ends in a circumferential direction of the tip portions of the teeth,
The slot insulating member includes a shoe covering portion of the slot inner circumferential wall that covers the shoe,
The stator of the electric motor according to claim 2 , wherein the pair of end surface insulating members are formed with slits for fixing both end portions of the shoe covering portion in the axial direction. the slot insulating member includes a back yoke covering portion that covers the back yoke in the slot inner wall, and a tooth covering portion that covers the teeth in the slot inner wall,
4. The stator of an electric motor as described in claim 2 or 3, wherein at least one of the set of end surface insulating members has a pressing portion formed to press a boundary portion between the tooth covering portion and the back yoke covering portion in the slot insulating member toward the split core side. An electric motor having the stator of the electric motor according to any one of claims 1 to 4 and a rotor rotatably provided with respect to the stator of the electric motor;
a compression element driven by the electric motor and compressing a refrigerant; A refrigeration cycle apparatus comprising: the compressor according to claim 5; a first heat exchanger; a decompression device; and a second heat exchanger, the first heat exchanger being connected by refrigerant piping to form a refrigerant circuit.

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