Stator and electric motor comprising the same

Abstract

The stator includes a stator core (13) having a substantially cylindrical back yoke (11) and a plurality of teeth (12) extending from the back yoke (11) toward a radially inner side. The stator core (13) is composed of a plurality of stator core pieces (13a) each including one tooth (12) and a yoke piece (11a) constituting a part of the back yoke (11). At a position more radially inward than the back yoke (11), adjacent ones of the stator core pieces (13a) are in contact with each other directly or through an intermediary.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a stator and an electric motor including the same. BACKGROUND

[0002] A stator core for an electric motor stator is configured so that a wire is wound in a straight bar core state, and then the straight bar core is crimped (bent) to become a substantially cylindrical shape (for example, Patent Document 1). In this configuration, only a portion of the outer circumferential side of the stator core is connected. Therefore, a compressive stress is generated with the portion as a fulcrum. This stress is a cause of deterioration of magnetic characteristics of the stator and the like, and therefore a technique for relieving the stress has been proposed.

[0003] For example, in Patent Document 1, a slit 8 is provided on both sides of a thin-walled portion 7 of a back yoke portion for bending the stator core 1. It is described therein that the stator core is easily bent and residual stress can be reduced by this.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: International Publication WO2012 / 105262 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] In the above-described configuration, since the slit is provided, the cross-sectional area of the back yoke portion is reduced, and the magnetic path width is reduced. As a result, magnetic saturation is easily caused, and further, iron loss increases.

[0009] An object of the present disclosure is to provide a stator core that can relieve stress without reducing the cross-sectional area of a back yoke portion.

[0010] SOLUTION TO THE PROBLEMS

[0011] A first aspect of the present disclosure is directed to a stator including a stator core 13 having a substantially cylindrical back yoke 11 and a plurality of teeth 12 extending from the back yoke 11 toward a radially inner side. The stator core 13 is configured by a plurality of stator core pieces 13a each including one tooth 12 and one yoke piece 11a constituting a portion of the back yoke 11. At a position more radially inward than the back yoke 11, adjacent stator core pieces 13a contact each other directly or through an intermediary.

[0012] In the first aspect, since the stator core pieces 13a contact each other at a position more radially inward than the back yoke 11, stress around the connection portions of the yoke pieces 11a to each other is relieved.

[0013] A second aspect of the present disclosure is, in the above-described first aspect, the teeth 12 include tooth extensions 16 extending in the circumferential direction of the back yoke 11, and the tooth extensions 16 in the adjacent stator core pieces 13a contact each other.

[0014] In the second aspect, the tooth extensions 16 contact each other, whereby stress in the vicinity of the connecting portions of the yoke pieces 11a to each other is mitigated.

[0015] A third aspect of the present disclosure is, in the above-described first aspect, the stator core pieces 13a further have yoke extensions 31 extending from the back yoke 11 toward the radially inner side, and the yoke extensions 31 in the adjacent stator core pieces 13a contact each other.

[0016] In the third aspect, the yoke extensions 31 contact each other, whereby stress in the vicinity of the connecting portions of the yoke pieces 11a to each other is mitigated.

[0017] A fourth aspect of the present disclosure is, in the above-described second or third aspect, the tooth extensions 16 or the yoke extensions 31 have portions in which the width narrows.

[0018] In the fourth aspect, the portions in which the width narrows are provided, whereby it is possible to suppress the propagation of stress toward the teeth 12 or the back yoke 11.

[0019] A fifth aspect of the present disclosure is, in the above-described any one of the second to fourth aspects, the stator core 13 has a structure in which a plurality of electromagnetic steel sheets cut into the same shape are laminated, and each electromagnetic steel sheet has a bent portion 23 at a portion corresponding to the tooth extension 16 or the yoke extension 31, the bent portion 23 being bent in a manner projecting in the axial direction of the back yoke 11 which is substantially cylindrical.

[0020] In the fifth aspect, the bent portion 23 is provided, whereby it is possible to suppress the propagation of stress toward the teeth 12 or the back yoke 11.

[0021] A sixth aspect of the present disclosure is, in the above-described first aspect, an insulator 14 covering at least a portion of each stator core piece 13a is provided, and the adjacent stator core pieces 13a contact each other with the insulator 14 as an intermediary.

[0022] In the sixth aspect, the stator core pieces 13a contact each other with the insulator 14 as an intermediary, whereby stress in the vicinity of the connecting portions of the yoke pieces 11a to each other is mitigated.

[0023] The seventh aspect of the present disclosure is, on the basis of the first aspect described above, that the plurality of teeth 12 are each provided with a coil 15 and a slot unit 33, adjacent stator core pieces 13a contact each other with both the coil 15 and the slot unit 33 as intermediaries, or contact each other with only the slot unit 33 as an intermediary, the slot unit 33 insulating the coil 15 from the teeth 12 and insulating the coils provided on the adjacent stator core pieces 13a from each other.

[0024] In the seventh aspect, the stator core pieces 13a contact each other with the slot unit 33, the coil 15 as intermediaries, whereby stress in the vicinity of the connection portions of the yoke pieces 11a to each other is alleviated.

[0025] The eighth aspect of the present disclosure relates to an electric motor including the stator of any one of the first to seventh aspects described above, and including a rotor on the inner side of the stator, the rotor being provided on the same axis as the stator.

[0026] In the eighth aspect, the performance of the electric motor is improved due to the improvement in the magnetic characteristics of the stator of the first to seventh aspects. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a cross-sectional view schematically showing a stator of a first embodiment of the present disclosure;

[0028] Figure 2 is a view showing Figure 1 a stator core in the stator of

[0029] Figure 3 is a view showing a straight core constituting Figure 2 a stator core by being crimped;

[0030] Figure 4 is a view showing a case where the tooth extensions contact each other when the straight core of Figure 3 is crimped;

[0031] Figure 5 is a view showing a case where the tooth extensions protrude more than the extension surface of the yoke end portion;

[0032] Figure 6 is a view showing an example in which a recess is provided on the tooth extension;

[0033] Figure 7 is a view showing an example in which the stator core has a laminated structure of electromagnetic steel sheets, and the electromagnetic steel sheets have a bent structure at a portion corresponding to the tooth extension;

[0034] Figure 8 is a view exemplarily showing a bent structure of the tooth extension and a recess;

[0035] Figure 9 This is an exemplary diagram showing an example of multiple bends in the tooth extension;

[0036] Figure 10 This is a diagram showing the case in the second embodiment where a yoke extension is provided on the stator iron chip;

[0037] Figure 11 This diagram shows the situation where the extensions of the yoke come into contact with each other after the coiling process.

[0038] Figure 12 This is a diagram showing the stator iron chip including the insulator in the third embodiment;

[0039] Figure 13 This diagram shows the stator iron laminations in contact with each other after being coiled, with an insulator as the medium.

[0040] Figure 14 This is a diagram showing a stator iron chip including slot units and coils according to the fourth embodiment;

[0041] Figure 15 This diagram shows the situation where the stator iron chips are in contact with each other after being coiled, with slot cells and coils as intermediaries;

[0042] Figure 16 It shows including Figure 1 A diagram of the stator of an electric motor. Detailed Implementation

[0043] (First Implementation)

[0044] The first embodiment is described below. The stator 10 includes a stator core 13 having a generally cylindrical back yoke 11 and a plurality of teeth 12 extending radially inward from the back yoke 11. The stator core 13 is composed of a plurality of stator laminations 13a, each stator lamination 13a including a tooth 12 and a magnetic yoke piece 11a forming part of the back yoke 11. At a position further radially inward than the back yoke 11, adjacent stator laminations 13a are in direct contact with each other or in contact with each other through an intermediary.

[0045] More specifically, Figure 1 This is a schematic cross-sectional view of the stator 10 according to this embodiment. The stator 10 includes a stator core 13 and a coil 15.

[0046] The stator core 13 includes a generally cylindrical back yoke 11 and a plurality of teeth 12 extending radially inward from the back yoke 11 toward the stator core 13. A winding is wound on each tooth 12 to form a coil 15. The stator core 13 and the coil 15 are electrically insulated from each other by an insulator 14 and slot units (not shown).

[0047] then,Figure 2 This diagram further illustrates the stator core 13. The stator core 13 is composed of multiple stator core pieces 13a. Each stator core piece 13a includes a yoke plate 11a and teeth 12 that form part of the back yoke 11. The yoke plates 11a in the multiple stator core pieces 13a are connected by narrow connecting portions to form a generally cylindrical back yoke 11. As a result, the teeth 12 are positioned to extend radially inward toward the back yoke 11.

[0048] Tooth extensions 16 are provided at the top of the radially inner side of the tooth 12, extending circumferentially along the back yoke 11. The tooth extensions 16 included in adjacent stator iron chips 13a are in contact with each other.

[0049] It should be noted that in this application, "generally cylindrical" refers to a shape that is generally identified as cylindrical, and does not necessarily have to be a "cylinder" in a strictly mathematical sense. For example, there may be unevenness, deformation, etc., which may be caused by the precision of the processing, the processing method, etc., or may be understood as acceptable as common technical knowledge. The same applies when simply describing it as "cylindrical". Similarly, "generally circular" does not necessarily have to be a "circle" in mathematical sense.

[0050] Figure 2 The stator core 13 is constructed by... Figure 3 The straight iron core 13b shown in its linear extension state is constructed by winding (bending). It should be noted that the winding is performed after the insulator 14, coil 15, etc., are arranged on the straight iron core 13b. Figure 3 Not shown in the figure. Furthermore, as a result of this configuration, the cross-sectional shape of the outer peripheral surface of the stator core 13 can also be a polygon with rounded edges on each side. (In this case, the stator core 13 is also considered to be approximately cylindrical).

[0051] In the straight iron core 13b, the magnetic yoke pieces 11a are connected to each other in a generally straight line. At the connection portion 17 where the stator iron core pieces 13a connect to each other (the magnetic yoke pieces 11a connect to each other), because there is a notch 18 in the shape of a triangle starting from the tooth 12 side, the width of the connection portion 17 is narrowed, so that it can be bent in a way that the tooth 12 side is the inside, forming a generally cylindrical stator iron core 10.

[0052] As described above, it is formed by curling. Figure 2 When the stator core 13 is in its normal state, the tooth extensions 16 are in contact with each other. This is achieved by providing tooth extensions 16 of appropriate length. The tooth extensions 16 are in contact with each other, thereby maintaining the back yoke 11 in a generally cylindrical shape. Therefore, stress concentration near the connection portion 17 in the back yoke 11 and on the end 11b of the magnetic yoke can be avoided.

[0053] Reference is made to Figure 4 This will be described. In Figure 4 Two adjacent stator core pieces 13a (half of each is shown) in the state after the curling of the stator core 13 are shown in FIG. 6. Note that the curling is performed in a state including the insulator 14, the coil 15, etc., but only the stator core 13 is shown in the figure.

[0054] In the curling of the straight core 13b of Figure 3 the back yoke 11 is mainly bent at the narrow-width connection portions 17. At this time, the tips of the tooth extensions 16 contact each other, thereby holding the positions of the adjacent stator core pieces 13a to each other, and the back yoke 11 as a whole is configured to be substantially cylindrical. Further, although the notches 18 are narrowed by the curling, it is possible to avoid the end portions of the adjacent yoke pieces 11a from contacting each other. As a result, it is possible to avoid the yoke pieces 11a from contacting each other and applying force to each other, resulting in stress concentration near the connection portions 17 and on the yoke end portions 11b. Note that depending on the length of the tooth extensions 16, it is also possible that the gap of the notches 18 disappears in the state where the tooth extensions 16 contact each other, and the end portions of the yoke pieces 11a contact each other. In this case, compared to the case where the tooth extensions 16 do not contact each other (and thus do not contribute to the shape maintenance of the back yoke 11), it is also possible to alleviate the stress concentration at the connection portions 17 and the yoke end portions 11b.

[0055] As described above, it is possible to suppress the rise of stress near the connection portions 17 and on the yoke end portions 11b in the back yoke 11. This makes it possible to suppress the deterioration of the magnetic characteristics, and further, to suppress the increase of the iron loss.

[0056] Further, unlike the case where a slit (for alleviating stress at the time of curling) is provided on the back yoke 11, the cross-sectional area of the back yoke 11 does not become small. Therefore, there is also no reduction in the magnetic path width due to the slit, and thus it is possible to avoid the increase of the iron loss due to magnetic saturation.

[0057] Further, in the portion where the tooth extensions 16 of the adjacent stator core pieces 13a contact each other in order to maintain the stator core 13 to be substantially cylindrical, the stress is concentrated and becomes large. The contact portions of the tooth extensions 16 to each other become a passage of the magnetic flux, but since the stress is large, the magnetic characteristics of the contact portions of the tooth extensions 16 to each other deteriorate, and the passage of the magnetic flux is suppressed.

[0058] When the stator core 13 is combined with a rotor to configure a motor, if the magnetic flux generated by the magnet of the rotor passes through the tooth extensions 16, it becomes leakage magnetic flux that does not contribute to the rotation of the rotor. However, as described above, since the passage of the magnetic flux at the contact portions of the tooth extensions 16 is suppressed, the leakage magnetic flux and the reduction of the torque due thereto are suppressed.

[0059] Further, if the tooth extensions 16 do not contact each other and there is a space between the tips of the teeth 12, the magnetic permeability greatly differs between the portions of the teeth 12 and the portions of the space between the teeth 12, so it becomes a cause of torque fluctuation. In contrast, the tooth extensions 16 contact each other, so the variation range of the magnetic permeability is small, and torque fluctuation can be reduced compared to the case where the tooth extensions 16 do not contact each other.

[0060] Next, Figure 5 is a view schematically showing a range in the straight bar core 13b corresponding to two stator core pieces 13a. When the straight bar core 13b is coiled, for example, it is bent in a manner that the yoke end portions 1 lb of the adjacent yoke pieces 11a contact each other. If the tooth extensions 16 are made to protrude more than the extension plane (indicated as an extension line 20 in the drawing) of the yoke end portions 1 lb, the tooth extensions 16 contact each other when coiling is performed as described above. It can also be considered that the tooth extensions 16 are forced against each other and some degree of deformation occurs. Further, it can also be considered that if the amount of protrusion from the extension line 20 is large, a gap will be left between the yoke end portions 1 lb.

[0061] In Figure 5 , a claw-like shape of a triangle is provided at the tip of the tooth extension 16. However, various shapes can be adopted for the tip of the tooth extension 16. In particular, the tooth extension 16 preferably has a portion where the width narrows due to a recess being provided. As an example of the shape of the recess 21, a semicircle as indicated by A, a triangle as indicated by B, and a quadrangle as indicated by C are shown in Figure 6 . These shapes are examples, and other shapes can also be adopted.

[0062] In this way, if a portion of narrow width is provided on the tooth extension 16, stress due to the tooth extensions 16 contacting each other concentrates on the portion of narrow width. As a result, the stress can be suppressed from propagating toward the teeth 12 side of the tooth extension 16. Thus, deterioration of the magnetic characteristics due to stress at the teeth 12 can be suppressed.

[0063] Bending structure of tooth extension

[0064] Next, a structure as shown in Figure 7 will be described. A recess and protrusion can also be provided at a position of the tooth extension 16 in the direction of the center axis of the substantially cylindrical back yoke 11. This structure can also be realized by configuring the stator core 13 by laminating a plurality of electromagnetic steel sheets.

[0065] In this case, the stator core 13 has a structure in which a plurality of electromagnetic steel sheets cut into the same shape are laminated, and each electromagnetic steel sheet has a bent portion 23 at a position corresponding to the tooth extension 16, the bent portion 23 being bent in a manner that it protrudes in the axial direction of the substantially cylindrical back yoke 11.

[0066] In Figure 7 A bending structure 22 (X) of the tooth extension 16 on a piece of electromagnetic steel sheet after punching processing is schematically shown. Here, only one half of each of two adjacent stator core pieces 13a is shown, and in addition, a portion (Y) of the bending structure 22 is shown enlarged. Further, a state after laminating pieces of electromagnetic steel sheets in X is shown in Z. Figure 7 A state of a straight bar core 13b before being curled is shown.

[0067] By providing the above-described bending structure 22, stress generated due to the tooth extensions 16 contacting each other can also be concentrated in this portion. Thus, as in the case of providing the recess 21, stress can be inhibited from propagating toward the tooth 12 side, which leads to deterioration of magnetic characteristics.

[0068] Note that both the bending structure 22 and the recess 21 can be provided. Figure 8 Examples are shown.

[0069] In Figure 8 , the tooth extension 16 has a bending portion 23 that is bent and inclined in the thickness direction of the electromagnetic steel sheet (axial direction of the stator core 13) near the tip end. In D, a recess 21 is provided at the boundary between the bending portion 23 and the portion that is not bent. Figure 7 This case is shown.

[0070] Further, E also shows the same portion as D, but a recess 21 is provided on the position on the opposite side of the tooth extension 16 compared to the example of D. In the example of F, the recess 21 is provided on both sides of the tooth extension 16.

[0071] In this way, if the recess 21 is provided at the position coinciding with the bending portion 23, stress can be further concentrated, and thus this is preferable. However, the recess 21 can also be provided only at the portion that does not coincide with the bending portion 23. Further, a plurality of recesses 21 can also be provided. In Figure 8 G of shows an example in which, in addition to the recess 21 being provided at the position coinciding with the bending portion 23, recesses 21 are also provided at other positions.

[0072] Further, in Figure 7 and Figure 8 , there is only one region that is bent and inclined. However, the bending can also be performed multiple times. In Figure 9 , an example in the case described above is shown. In Figure 9 , there is a structure in which the tooth extension 16 is bent once in each of opposite directions near the tip end.

[0073] (Second Embodiment)

[0074] Reference is made to Figure 10 andFigure 11 The second embodiment will be described. The stator and the stator core of the present embodiment are also substantially the same as those of the first embodiment shown in FIG. 1. Figure 1 and Figure 2 The stator 10 and the stator core 13 of the present embodiment are substantially the same as those of the first embodiment shown in FIG. 1. That is, the stator core is constituted by the stator core pieces 13a including the yoke pieces 11a and the teeth 12, and is configured so that the back yoke 11 is in a cylindrical shape. Further, each tooth 12 includes the coil 15 through the insulator 14. The coil 15 is provided in the state of the straight core 13b, and is formed in the cylindrical stator by crimping. Figure 1 The cylindrical stator shown in FIG. 1 is also the same as the first embodiment.

[0075] However, in the present embodiment, the tooth extension 16 which contacts each other is not provided on the stator core piece 13a. Instead, the stator core piece 13a further has a yoke extension 31 which extends from the back yoke 11 toward the radially inner side, and the yoke extensions 31 in the adjacent stator core pieces 13a contact each other. Figure 10 , Figure 11 ).

[0076] This will be further described. Figure 10 Two adjacent stator core pieces 13a in the state of the straight core 13b are shown. On the stator core piece 13a, the yoke extension 31 is provided in a manner of extending from the yoke piece 11a toward the tooth 12 side (the inner side of the stator core 13 after crimping). The yoke extension 31 is formed so as to oppose the yoke extension 31 in the adjacent stator core piece 13a, and protrude more than the extension surface of the yoke end portion 11b (indicated as an extension line 20 in the figure). Therefore, when the straight core 13b is crimped to make the cylindrical stator core 13, the yoke extensions 31 in the adjacent stator core pieces 13 contact each other. This is shown in FIG. 2. Figure 11

[0077] Figure 11 Corresponds to the first embodiment. Figure 4 In the present embodiment, the tooth extension 16 which contacts each other is not provided. Instead, the yoke extension 31 is provided, and contacts each other at the time of crimping. In this way, the positions of the adjacent stator core pieces 13a are maintained from each other, and the back yoke 11 is constituted as a substantially cylindrical shape as a whole. As a result, the stress concentration around the connection portion 17 and at the yoke end portion 11b can be alleviated, and the deterioration of the magnetic characteristics and the increase of the iron loss can be suppressed.

[0078] In the present embodiment, Figure 10 , Figure 11 ​In this example, the yoke extension 31 is L-shaped. The yoke extension 31 extends in the same direction as the extension direction of the tooth 12 (towards the radially inner side of the stator core 13), and further extends along the direction of the yoke piece 11a in a manner opposite to the yoke extension 31 of the adjacent stator core piece 13a. However, this is just one example, and other shapes are also possible. For example, it could be a shape that is gently bent into an arc.

[0079] Furthermore, the yoke extension 31 may also be provided with a recess 21 and a bending structure 22 (bending portion 23) in the same manner as the tooth extension 16 in the first embodiment.

[0080] In this case, the stator core 13 has a structure formed by stacking multiple electromagnetic steel plates cut into the same shape, each electromagnetic steel plate having a bent portion 23 at the part corresponding to the magnetic yoke extension 31, the bent portion 23 being bent in such a way that it protrudes along the axial direction of the generally cylindrical back yoke 11.

[0081] Regarding the tooth extension 16, and Figure 6 to 9 As shown, the bent portion 23 and the recess 21 can be provided in combination, or only one of them can be provided. In addition, one or more of the bent portion 23 and the recess 21 can be provided.

[0082] By providing the recess 21 and / or the bending structure 22, the area of ​​stress concentration can be controlled. In particular, stress propagation to the magnetic yoke 11a can be suppressed, thereby suppressing the deterioration of the magnetic properties of the magnetic yoke 11a.

[0083] (Third Implementation)

[0084] Reference Figure 12 and Figure 13 The third embodiment will be described. The stator and stator core of this embodiment are also similar to... Figure 1 and Figure 2 The stator 10 and stator core 13 of the first embodiment shown are basically the same. That is, the stator core is composed of a plurality of stator core pieces 13a including magnetic yoke pieces 11a and teeth 12, and the back yoke 11 is configured to be cylindrical.

[0085] However, in this embodiment, tooth extensions 16 (and yoke extensions 31 in the second embodiment) that are in contact with each other are not provided on the stator iron chip 13a.

[0086] Instead, each of the stator laminations 13a is provided with an insulator 14 covering at least a portion thereof, and adjacent stator laminations 13a are in contact with each other through the insulator 14. When the stator 10 is formed by winding to include coils 15 and insulators 14, the insulators 14 respectively provided on adjacent stator laminations 13a are in contact with each other.Figure 12 This situation is illustrated in the image.

[0087] Figure 12 The diagram shows two adjacent stator cores 13a in the state of a straight bar core 13b. Each stator core 13a has an insulator 14 that insulates the coil 15 (not shown) from the stator core 13a. The insulator 14 includes an insulator extension 32 at the tip of the tooth 12, which extends along the extension direction of the yoke 11a (or the circumferential direction of the stator core 13 after curling). The insulator extension 32 is formed opposite to the insulator extension 32 in the adjacent stator core 13a and protrudes beyond the extended surface of the yoke end 11b (shown as extension line 20 in the diagram). Therefore, when the straight bar core 13b is curled to form a cylindrical stator core 13, the insulator extensions 32 in the adjacent stator cores 13 come into contact with each other. Figure 13 This situation is illustrated in the image.

[0088] Figure 13 Compared with the first embodiment Figure 4 Corresponding. In Figure 13 The diagram shows insulator 14, but coil 15 is omitted.

[0089] In this embodiment, the stator core 13a does not have tooth extensions 16 (and yoke extensions 31) that contact each other. Instead, after curling, the insulator extensions 32 of the insulator 14 on each stator core 13a contact each other. That is, after the straight core 13b is curled, the stator cores 13a are indirectly in contact through the insulator 14 (insulator extensions 32), instead of having a portion other than the connecting portion 17 where the stator cores 13a directly contact each other after the straight core 13b is curled. In this way, the position of adjacent stator cores 13a is maintained, and the back yoke 11 is generally cylindrical. As a result, stress concentration near the connecting portion 17 and at the yoke end 11b can be alleviated, and the deterioration of magnetic properties and the increase of iron loss can be suppressed.

[0090] (Fourth Implementation)

[0091] Reference Figure 14 and Figure 15 The fourth embodiment will be described. The stator and stator core of this embodiment are also similar to... Figure 1 and Figure 2 The stator 10 and stator core 13 of the first embodiment shown are basically the same. That is, the stator core is composed of a plurality of stator core pieces 13a including magnetic yoke pieces 11a and teeth 12, and the back yoke 11 is configured to be cylindrical.

[0092] However, in this embodiment, the stator iron chip 13a does not have tooth extensions 16 that are in contact with each other (as well as the magnetic yoke extensions 31 in the second embodiment).

[0093] Instead, coils 15 and slot units 33 are respectively provided on the plurality of teeth 12, and adjacent stator laminations 13a are in contact with each other by using both coils 15 and slot units 33 as intermediaries or only by using slot units 33 as intermediaries. The slot units 33 insulate the coils 15 from the teeth 12 and insulate the coils provided on adjacent stator laminations 13a from each other.

[0094] When the stator 10, which includes coils 15 and insulators 14, is formed by winding, the slot units 33 respectively provided on adjacent stator laminations 13a come into contact with each other. Here, the slot units 33 are configured to prevent the coils 15 on adjacent stator laminations 13a from directly contacting each other.

[0095] Figure 14 The diagram shows two adjacent stator cores 13a in the state of a straight bar core 13b. Each stator core 13a has a coil 15 mounted on a tooth 12 and a slot unit 33 that insulates the tooth 12 from the coil 15. The coil 15 and slot unit 33 are configured to protrude beyond the extended surface of the yoke end 11b (shown as extension line 20 in the figure). Therefore, when the straight bar core 13b is rolled into a cylindrical stator core 13, the coils 15 on adjacent stator cores 13 are in contact with each other across the slot unit 33. Figure 15 This situation is illustrated in the image.

[0096] Figure 15 Compared with the first embodiment Figure 4 Correspondingly, in this embodiment, the stator core 13a does not have tooth extensions 16 (and yoke extensions 31) that contact each other. Instead, after winding, the coils 15 provided on each stator core 13a contact each other with a gap of slot units 33 between them. That is, after the straight iron core 13b is wound, the stator core 13a are indirectly contacted by the coils 15 and slot units 33 as intermediaries, which is a solution that, apart from the connection part 17, is provided at the part where the stator core 13a directly contacts each other after the straight iron core 13b is wound. In this way, the position of adjacent stator cores 13a is maintained, and the back yoke 11 is generally cylindrical. As a result, stress concentration near the connection part 17 and at the end 11b of the yoke can be alleviated, and the deterioration of magnetic properties and the increase of iron loss can be suppressed.

[0097] - Variations of the fourth embodiment -

[0098] A variation of the fourth embodiment will be described. Figure 14 and Figure 15The coil 15 and the slot unit 33 both protrude beyond the extension surface (extension line 20) of the yoke end portion 1 lb in the state before the winding is crimped.

[0099] In contrast, in the modification, only the slot unit 33 protrudes beyond the extension line 20, and the coil 15 does not exceed the extension line 20 (converges to the side of each tooth 12). This can be understood as follows: in the modification, the portion of the winding in the coil 15, which is hatched, does not exist in the state (although not hatched, it is understood that the winding exists for the Figure 14 In the modification, the coil 15 of the left end and the right end is the same as well). However, the winding can be further reduced. Figure 14

[0100] In this case, when the straight core 13b is crimped, the stator core pieces 13a also contact each other indirectly with the slot unit 33 as an intermediary. In this way, the positions of the adjacent stator core pieces 13a are maintained with respect to each other, and the back yoke 11 as a whole is configured to be substantially cylindrical. As a result, stress concentration near the connection portion 17 and at the yoke end portion 1 lb can be alleviated, and deterioration of magnetic characteristics and an increase in iron loss can be suppressed.

[0101] (Other Embodiments)

[0102] Next, the motor using the stator core 13 of the present disclosure will be described with reference to Figure 16 Figure 16 is a diagram schematically showing a motor 40 using the stator 10 of the first embodiment. The stator core 13 is fixed to the inner peripheral surface of a cylindrical frame 41. In addition, a rotor 42 is provided on the inner side of the stator core 13, and the rotor 42 and the stator core 13 are located on the same axis.

[0103] The motor 40 having such a structure can exhibit improved performance due to the reduction in iron loss of the stator core 13 and the improvement in magnetic characteristics.

[0104] Note that, of course, a motor using the stator core 13 of the second to fourth embodiments can also exhibit improved performance, and individual diagrams are omitted here.

[0105] The embodiments and modifications have been described above, but it should be understood that various changes can be made to the modes and details thereof without departing from the spirit and scope of the claims. The above-described embodiments and modifications can also be appropriately combined or replaced as long as the function of the object of the present disclosure is not affected.

[0106] Industrial Applicability

[0107] As described above, the present disclosure is useful for a stator and a motor including the stator.

[0108] Explanation of Symbols​​

[0109] 10 stator

[0110] 11 back yoke

[0111] 11a yoke piece

[0112] 11b yoke end

[0113] 12 tooth

[0114] 13 stator core

[0115] 13a stator core piece

[0116] 13b straight bar core

[0117] 14 insulator

[0118] 15 coil

[0119] 16 tooth extension

[0120] 17 connection site

[0121] 20 extension wire

[0122] 21 recess

[0123] 22 bent structure

[0124] 23 bent portion

[0125] 31 yoke extension

[0126] 32 insulator extension

[0127] 33 slot unit

[0128] 40 motor

[0129] 41 frame

[0130] 42 rotor

Claims

1. A stator, characterized in that: The stator includes a stator core (13) having a generally cylindrical back yoke (11) and a plurality of teeth (12) extending radially inward from the back yoke (11). The stator core (13) is composed of a plurality of stator chips (13a), each of the plurality of stator chips (13a) including a tooth (12) and a magnetic yoke piece (11a) that forms part of the back yoke (11). At a position further radially inward than the back yoke (11), adjacent stator iron chips (13a) are in direct contact with each other or in contact with each other through an intermediary. The stator iron chip (13a) also has a magnetic yoke extension (31) that extends radially inward from the back yoke (11) independently of the tooth (12) and further extends circumferentially. The magnetic yoke extensions (31) in adjacent stator iron chips (13a) come into contact with each other, thereby preventing the ends of adjacent magnetic yoke pieces (11a) from coming into contact with each other.

2. The stator according to claim 1, characterized in that: The magnetic yoke extension (31) has a portion that is narrowed in width due to the presence of a recess (21).

3. The stator according to claim 1, characterized in that: The stator core (13) has a structure formed by stacking multiple electromagnetic steel plates cut into the same shape. Each of the electromagnetic steel plates has a bent portion (23) at the top end of the portion corresponding to the magnetic yoke extension (31), the bent portion (23) being bent in such a way that it protrudes along the axial direction of the generally cylindrical back yoke (11).

4. A stator, characterized in that: The stator includes a stator core (13) having a generally cylindrical back yoke (11) and a plurality of teeth (12) extending radially inward from the back yoke (11). The stator core (13) is composed of a plurality of stator chips (13a), each of the plurality of stator chips (13a) including a tooth (12) and a magnetic yoke piece (11a) that forms part of the back yoke (11). At a position further radially inward than the back yoke (11), adjacent stator iron chips (13a) are in direct contact with each other or in contact with each other through an intermediary. The tooth (12) includes a tooth extension (16) extending circumferentially along the back yoke (11) at its radially inner end. The tooth extensions (16) in adjacent stator iron laminations (13a) contact each other, thereby preventing the ends of adjacent magnetic yoke plates (11a) from contacting each other. The tooth extension (16) has a portion that is narrowed in width due to the presence of a recess (21).

5. A stator, characterized in that: The stator includes a stator core (13) having a generally cylindrical back yoke (11) and a plurality of teeth (12) extending radially inward from the back yoke (11). The stator core (13) is composed of a plurality of stator chips (13a), each of the plurality of stator chips (13a) including a tooth (12) and a magnetic yoke piece (11a) that forms part of the back yoke (11). At a position further radially inward than the back yoke (11), adjacent stator iron chips (13a) are in direct contact with each other or in contact with each other through an intermediary. The tooth (12) includes a tooth extension (16) extending circumferentially along the back yoke (11). The tooth extensions (16) in adjacent stator iron laminations (13a) contact each other, thereby preventing the ends of adjacent magnetic yoke plates (11a) from contacting each other. The stator core (13) has a structure formed by stacking multiple electromagnetic steel plates cut into the same shape. Each of the electromagnetic steel plates has a bent portion (23) at the top end of the portion corresponding to the tooth extension (16), the bent portion (23) being bent in such a way that it protrudes along the axial direction of the generally cylindrical back yoke (11).

6. The stator according to any one of claims 1, 4, and 5, characterized in that: An insulator (14) covering at least a portion of each of the stator iron chips (13a) is provided on each of the stator iron chips (13a). The adjacent stator iron chips (13a) are in contact with each other through the insulator (14) as the medium.

7. A stator, characterized in that: The stator includes a stator core (13) having a generally cylindrical back yoke (11) and a plurality of teeth (12) extending radially inward from the back yoke (11). The stator core (13) is composed of a plurality of stator chips (13a), each of the plurality of stator chips (13a) including a tooth (12) and a magnetic yoke piece (11a) that forms part of the back yoke (11). At a position further radially inward than the back yoke (11), adjacent stator iron chips (13a) are in direct contact with each other or in contact with each other through an intermediary. Coil (15) and slot unit (33) are respectively provided on the multiple teeth (12). The adjacent stator iron laminations (13a) are in contact with each other only through the slot unit (33) as the intermediary, thereby preventing the ends of the adjacent magnetic yokes (11a) from contacting each other. The slot unit (33) insulates the coil (15) from the tooth (12) and insulates the coils disposed on adjacent stator iron chips (13a) from each other.

8. An electric motor, characterized in that: include: The stator as described in any one of claims 1 to 7; as well as The rotor is disposed inside the stator, and the rotor and the stator are disposed on the same axis.

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