A straight-strip stator lamination, stator and motor

Abstract

This invention provides a straight stator lamination, a stator, and a motor. During the fabrication process, multiple stator lamination units are simultaneously fabricated, including a first stator lamination unit and a second stator lamination unit. One end of a first stator tooth is connected to a first stator yoke, and the other end extends away from the second stator lamination unit. One end of a second stator tooth is connected to a second stator yoke, and the other end extends away from the first stator lamination unit. The first stator yoke and the second stator yoke are connected and arranged in contact. The end face of the first stator yoke opposite to the first stator tooth is a second end face. The end face of the second stator yoke opposite to the second stator tooth is a fourth end face. The second end face and the fourth end face are adapted to each other and are fitted together. This invention effectively eliminates the overlap (bf2) between each group of stator laminations, improving material utilization and reducing stator costs.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a straight stator lamination, a stator, and a motor. Background Technology

[0002] Cost reduction is one of the important goals of motor research and development. Currently, electromagnetic technology in the field of wind turbine motors is relatively mature, and the products of various manufacturers are highly homogenized, making it difficult to achieve cost reduction through electromagnetic scheme optimization. Therefore, improving the material utilization rate of motors by reducing waste in the production process has become the main cost reduction route.

[0003] Existing stator designs generally fall into four categories: full-circle, segmented, coiled, and straight-bar. Full-circle stators have low material utilization and slow winding speed; segmented stators require individual winding for each stator unit, resulting in numerous and complex post-assembly processing of wire ends and low roundness accuracy; coiled stators have complex structures and are difficult to manufacture; straight-bar stators offer comprehensive advantages in all these aspects and are therefore the most widely used in wind turbine motors.

[0004] like Figure 1 As shown, traditional stator cores are generally laid out in an interlocking pattern, meaning two rows of stator laminations are interlocked and stamped simultaneously. According to the traditional stator core shape, two overlaps must be reserved during layout: one is the overlap between the two rows of stator laminations in a group, with a width of bf1; the other is the overlap between each group, with a width of bf2. The material utilization rate of a row of stator laminations...

[0005] =V1*2 / L1 / (b1+hj1+bf1+bf2), L1=(Z1+0.5)*L4+(6~9mm), where V1 is the practical area of ​​traditional stator laminations, b1 is the width of stator laminations, L1 is the width of the sample material, Z1 is the number of stator core teeth, L4 is the tooth pitch, and hj1 is the height of the yoke. Therefore, eliminating the overlap and shortening the stator core tooth pitch can greatly improve the material utilization rate of stator laminations.

[0006] Because existing technologies require leaving overlaps when arranging stator laminations, resulting in low material utilization, this invention researches and designs a straight-bar stator lamination, stator, and motor. Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defect of low material utilization caused by the need to reserve overlap when arranging stator laminations in the prior art, thereby providing a straight stator lamination, stator and motor.

[0008] To address the above problems, the present invention provides a straight stator lamination, comprising:

[0009] The straight stator laminations are fabricated simultaneously during the layout process to produce multiple stator lamination units. The multiple stator lamination units have the same structure and include a first stator lamination unit and a second stator lamination unit.

[0010] The first stator lamination unit includes a first stator tooth and a first stator yoke. One end of the first stator tooth is connected to the first stator yoke, and the other end extends outward from the second stator lamination unit. The second stator lamination unit includes a second stator tooth and a second stator yoke. One end of the second stator tooth is connected to the second stator yoke, and the other end extends outward from the first stator lamination unit. The first stator yoke and the second stator yoke are connected to each other.

[0011] The first stator yoke is configured such that the end face of the first stator tooth is the first end face, and the end face opposite to the first stator tooth is the second end face; the second stator yoke is configured such that the end face of the second stator tooth is the third end face, and the end face opposite to the second stator tooth is the fourth end face; the second end face and the fourth end face are adapted to each other and are fitted together.

[0012] The first stator lamination unit is multiple, and the multiple first stator lamination units are connected sequentially to form the straight stator lamination, and the first stator lamination unit at the beginning end is connected to the first stator lamination unit at the end end to form a ring-shaped stator lamination structure.

[0013] The first stator yoke has an inner surface boss that protrudes outward on the first end face, and the height of the inner surface boss from the first end face is the height h2 of the inner surface boss.

[0014] The inner surface bosses of the yokes of two adjacent first stator yokes are provided with connecting grooves at the joint, and a sink groove is also provided at the top of the connecting groove to form a first process groove.

[0015] In some embodiments, a third stator lamination unit is also included, wherein the third stator lamination unit, the first stator lamination unit, and the second stator lamination unit are connected in sequence;

[0016] The third stator lamination unit includes a third stator tooth and a third stator yoke. One end of the third stator tooth is connected to the third stator yoke, and the other end extends toward the first stator yoke and is connected to the first stator yoke. The first stator tooth extends toward the third stator yoke and is connected to the third stator yoke.

[0017] The third stator yoke is configured such that the end face of the third stator tooth is the fifth end face, and the end face opposite to the third stator tooth is the sixth end face; the free end face of the first stator tooth is adapted to and fits against the fifth end face, and the free end face of the third stator tooth is adapted to and fits against the first end face.

[0018] In some embodiments, there are multiple second stator lamination units connected sequentially; there are multiple third stator lamination units connected sequentially; the first stator tooth is inserted between two adjacent third stator teeth, and the third stator tooth is inserted between two adjacent first stator teeth, forming an interlocking arrangement structure.

[0019] In some embodiments, the free end face of the first stator tooth is a first arc-shaped surface, the fifth end face of the third stator yoke is a second arc-shaped surface, and the first arc-shaped surface and the second arc-shaped surface are in close contact; the free end face of the third stator tooth is a third arc-shaped surface, the first end face of the first stator yoke is a fourth arc-shaped surface, and the third arc-shaped surface and the fourth arc-shaped surface are in close contact.

[0020] In some embodiments, the first arc surface is a concave arc surface, the second arc surface is a convex arc surface, the third arc surface is a concave arc surface, and the fourth arc surface is a convex arc surface.

[0021] In some embodiments, during the fabrication of the layout, the second end face of the first stator yoke is a straight plane, and the fourth end face of the second stator yoke is a straight plane.

[0022] In some embodiments, the minimum distance between the connecting groove and the second end face is the yoke connection height h1; the width of the first process groove is b3; the distance between the first end face and the contact position of the inner surface boss of the yoke and the second end face is the yoke height hj2; the number of teeth of the first stator tooth is the number of stator core teeth Z1; and the above parameters satisfy the following relationship: b3=2*(hj2-h1+h2)*tan(180° / Z1)+(0.2~0.5)mm.

[0023] In some embodiments, a second process groove is provided on the free end face of the first stator tooth, the depth of the second process groove being t1 = 0.2~0.3mm; a process chamfer is provided at the junction of the first end face and the inner surface boss of the yoke, and the h2 is greater than the radius of the process chamfer.

[0024] In some embodiments, the tooth pitch between two adjacent first stator lamination units is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth. In the annular stator lamination structure, along the radial direction, the distance between the second end face and the center of the circle is the stator radius R. The number of teeth of the first stator teeth is the number of teeth of the stator core Z1. The above parameters satisfy the following relationship: L3=2*(R-h1-t3)*tan(180° / Z1).

[0025] In some embodiments, the layout width of the straight stator lamination is L2, where L2 is the length of the first stator lamination units connected sequentially, the number of teeth of the first stator tooth is the number of teeth of the stator core Z1, and the tooth pitch between two adjacent first stator lamination units is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth. The above parameters satisfy the following relationship: L2=(Z1+0.5)*L3+(6~9mm).

[0026] In some embodiments, a first protrusion is provided on the first stator yoke of the first stator lamination unit at the beginning end, protruding toward the first stator yoke of the first stator lamination at the end end, and a first groove is provided on the first stator yoke of the first stator lamination unit at the end end, in a direction away from the first stator yoke of the first stator lamination at the beginning end. The first protrusion can be inserted into the first groove to form a snap-fit.

[0027] In some embodiments, the first protrusion is an arc protrusion, the first groove is an arc groove, the width of the arc protrusion along the direction perpendicular to the first end face is b4, the distance between the first end face and the second end face of the first stator yoke is the yoke height hj2, and the number of teeth of the first stator tooth is the number of stator core teeth Z1. The above parameters satisfy the following relationship: b4=(20%~40%)*(hj2+h2) / tan(180° / Z1).

[0028] In some embodiments, a second protrusion is provided on the second end face of the first stator yoke of the first stator lamination unit at the beginning end, protruding in a direction away from the first end face; a third protrusion is provided on the second end face of the first stator yoke of the first stator lamination unit at the end end, protruding in a direction away from the first end face; the first contact surface is formed between the first protrusion and the first groove and the first end face, and the two first stator yokes are opposite and in contact; the side of the second protrusion and the side of the third protrusion are in contact to form a second contact surface, and the second contact surface and the first contact surface are located on different surfaces; the second contact surface is closer to the first stator tooth at the beginning end relative to the first contact surface; the second protrusion is a sharp-angled protrusion; the third protrusion is a protrusion formed smoothly on the second end face; the first process groove is located radially inside the first contact surface.

[0029] In some embodiments, both the first contact surface and the second contact surface pass through the center of the annular stator lamination structure, and the included angle between their centers is α; the protrusion height of the second protrusion is the same as that of the third protrusion, both being h3, and

[0030] h3 = 0.2 ~ 0.5 mm = R / cos(a + 180° / Z1) - R / cos(180° / Z1), where R is the distance between the second end face and the center of the circle, which is the stator radius.

[0031] In some embodiments, the first stator tooth includes a stator tooth body and a pole shoe. One end of the pole shoe is connected to the circumferential side of the stator tooth body and is located at the position furthest from the first stator yoke. The other end extends in the circumferential direction. There are two pole shoes, which are arranged one-to-one with the circumferential sides of the stator tooth body.

[0032] A first fastening point is provided on the end face of the stator tooth body, and a reserved groove is provided on both sides of the first fastening point. The depth of the reserved groove is t2. A second fastening point is provided on the end face of the first stator yoke.

[0033] In some embodiments, the circumferential width of the stator tooth body is the tooth width bt, and satisfies the relationship: t2 = (1% ~ 2%) * bt / 2.

[0034] In some embodiments, after the annular stator lamination structure is formed, the first stator tooth is located radially inside the first stator yoke, i.e., the stator core for an inner rotor motor.

[0035] The present invention also provides a stator comprising the straight stator laminations described in the preceding claim.

[0036] The present invention also provides an electric motor comprising the aforementioned stator.

[0037] The straight-strip stator lamination, stator, and motor provided by this invention have the following beneficial effects:

[0038] 1. This invention, by designing multiple identical stator lamination units in the straight-strip stator lamination fabrication process, and having the first stator yoke of the first stator lamination unit and the second stator yoke of the second stator lamination unit fit together, and the second end face of the first stator yoke and the fourth end face of the second stator yoke mutually adapt and fit together, effectively eliminates the original overlap bf2 between each group of stator laminations. Eliminating this overlap structure allows the opposing end faces of the two groups of stator yokes to fit together, thus achieving… To effectively improve material utilization, the outer surface of the yoke of the preferred straight stator lamination is a straight surface. During layout, no overlap is required between each group of stator laminations, thus improving material utilization and reducing stator costs. Furthermore, by adapting and fitting the free end face of the first stator tooth of the first stator lamination unit to the fifth end of the third stator yoke of the third stator lamination unit, and the free end face of the third stator tooth to the first end of the first stator yoke, the invention effectively eliminates the need for two rows of stator yokes in a single unit. The pre-reserved overlap (bf1) between stator laminations further improves material utilization. Specifically, the inner diameter surface of the straight stator laminations in this invention is aligned with the inner surface of the yoke for layout, eliminating the need for pre-reserved overlap between rows of stator laminations, thus improving material utilization and reducing stator costs. Furthermore, this invention features a first process groove at the junction of the inner diameter surface of the stator lamination and the yoke, specifically at the top of the connecting groove. This allows for better penetration of machine oil into the lamination material during stamping, preventing damage to the cutting tools and laminations, and solving the stator stamping problem. The process groove can prevent the stator lamination from having long, thin excess material at the corners after stamping, thus avoiding secondary processing and solving the problem of excess material at the corners after stamping. The process groove also reduces the cogging torque and torque pulsation of the motor, solving the problem of large cogging torque and large torque pulsation. In other words, the process groove at the yoke connection can effectively reduce the cogging torque and torque pulsation, and also effectively prevent the problem of magnetic saturation.

[0039] 2. The present invention further provides that the width of the first process groove satisfies the following relationship: b3=2*(hj2-h1+h2)*tan(180° / Z1)+(0.2~0.5)mm, and the depth of the second process groove on the inner diameter surface is t1=0.1~0.3mm, which can effectively reduce the cogging torque and torque pulsation of the motor and avoid secondary processing;

[0040] 3. The straight bar stator core of the present invention has matching arc protrusions and arc grooves at the joints on both sides, which can effectively avoid cracking after the straight bar stator core is rounded (the existing structure has a straight line crack, which is easy to crack under welding stress; the present invention uses the cooperation of protrusions and grooves and forms an offset angle during the stamping process, so the crack is not a straight line, so it is not easy to crack). It can effectively ensure the rounding accuracy of the stator core and solve the problem of low stator roundness caused by cracking after the stator core is rounded.

[0041] 4. After the stator core of the present invention is formed into a circle, there is a protruding structure outside the joint, which is beneficial to the welding process. The welding process only has one step, resulting in high production efficiency. This solves the problem of low production efficiency due to the large number of welding steps after the stator core is formed into a circle. The stator lamination teeth have reserved grooves on both sides of the snap point position to ensure that the tooth width dimension does not exceed the tolerance range after the snap point is stamped, thereby improving the product qualification rate and solving the problem that the stator tooth width dimension becomes larger after the stator lamination is stamped and snapped.

[0042] 5. In this invention, the stator core teeth are located inside the yoke, i.e., the stator core for an inner rotor motor. After the straight stator core is rounded, the slot width is ensured to be not too large, thus improving the performance of the motor. This solves the problem that the motor performance is reduced due to the excessive slot width after the stator core is rounded. Attached Figure Description

[0043] Figure 1 This is a layout diagram of the existing straight bar stator core;

[0044] Figure 2 This is a diagram showing the layout structure of the straight bar stator core of the present invention;

[0045] Figure 2a yes Figure 2 A magnified view of part O in the middle;

[0046] Figure 3 This is a diagram showing the circular structure of the straight bar stator core of the present invention;

[0047] Figure 4 This is a partially enlarged view of the straight bar stator core of the present invention;

[0048] Figure 4a for Figure 4 A magnified view of the yoke joint (point A);

[0049] Figure 4b for Figure 4 A magnified view of the yoke junction (at point E);

[0050] Figure 5 This is a partial enlarged view of the straight bar stator core of the present invention at the joint;

[0051] Figure 5a yes Figure 5 A close-up view of the seam (point B);

[0052] Figure 6 This is a structural diagram of two stator lamination units connected together when there are no process slots and no yoke bosses in the existing straight bar stator core.

[0053] Figure 6a yes Figure 6 A magnified view of part C;

[0054] Figure 6b yes Figure 6 A magnified view of part D.

[0055] The reference numerals in the attached figures are as follows:

[0056] 101. First stator lamination unit; 102. Second stator lamination unit; 1. First stator tooth; 2. First stator yoke; 21. First end face; 22. Second end face; 3. Second stator tooth; 4. Second stator yoke; 41. Third end face; 42. Fourth end face; 103. Third stator lamination unit; 5. Third stator tooth; 6. Third stator yoke; 61. Fifth end face; 62. Sixth end face; 7. First process groove; 8. Boss on inner surface of yoke; 9. Connecting groove; 10. Second process groove; 11. First protrusion; 12. First groove; 13. Second protrusion; 14. Third protrusion; 15. First contact surface; 16. Second contact surface; 17. Stator tooth body; 18. Pole shoe; 191. First fastening point; 192. Second fastening point; 20. Reserved groove; 20a. Slender excess material. Detailed Implementation

[0057] like Figure 2-5 As shown, the present invention provides a straight stator lamination, comprising:

[0058] The straight stator lamination is fabricated simultaneously during the layout process, with multiple stator lamination units having the same structure. The multiple stator lamination units include a first stator lamination unit 101 and a second stator lamination unit 102.

[0059] The first stator lamination unit 101 includes a first stator tooth 1 and a first stator yoke 2. One end of the first stator tooth 1 is connected to the first stator yoke 2, and the other end extends outward from the second stator lamination unit 102. The second stator lamination unit 102 includes a second stator tooth 3 and a second stator yoke 4. One end of the second stator tooth 3 is connected to the second stator yoke 4, and the other end extends outward from the first stator lamination unit 101. The first stator yoke 2 and the second stator yoke 4 are connected to each other.

[0060] The first stator yoke 2 is configured such that the end face of the first stator tooth 1 is the first end face 21, and the end face opposite to the first stator tooth 1 is the second end face 22; the second stator yoke 4 is configured such that the end face of the second stator tooth 3 is the third end face 41, and the end face opposite to the second stator tooth 3 is the fourth end face 42; the second end face 22 and the fourth end face 42 are adapted to each other and are fitted together.

[0061] The first stator lamination unit 101 is multiple, and the multiple first stator lamination units are connected sequentially to form the straight stator lamination, and the first stator lamination unit at the beginning end is connected to the first stator lamination unit at the end end to form a ring-shaped stator lamination structure.

[0062] The first stator yoke 2 has an inner surface boss 8 protruding outward on the first end face 21, and the height of the inner surface boss 8 from the first end face 21 is the height h2 of the inner surface boss.

[0063] The inner surface bosses 8 of the two adjacent first stator yokes 2 are provided with connecting grooves 9 at the joint, and a sink groove is also provided at the top of the connecting groove 9 to form a first process groove 7.

[0064] This invention utilizes identical stator lamination units in the layout process of straight stator laminations. The first stator yoke of the first stator lamination unit and the second stator yoke of the second stator lamination unit are designed to fit together, with the second end face of the first stator yoke and the fourth end face of the second stator yoke mutually adapting and fitting together. This effectively eliminates the original overlap (bf2) between each group of stator laminations, allowing the opposite end faces of the two groups of stator yokes to fit together. This significantly improves material utilization. Preferably, the outer surface of the yoke of the straight stator lamination is a straight surface, eliminating the need for pre-reserved overlap between each group of stator laminations during layout, thus increasing material utilization and reducing stator costs. This invention also features a first process groove at the junction of the inner diameter surface of the stator lamination and the yoke, specifically at the top of the connecting groove. This allows the machine oil to better penetrate the lamination material during stamping, preventing damage to the cutting tools and laminations, thus solving the problem of tool and lamination damage during stator lamination stamping. The process groove also prevents long, thin excess material from remaining at the corners of the stator lamination after stamping, avoiding secondary processing and solving the problem of excess material requiring secondary processing. Furthermore, the process groove weakens the cogging torque and torque pulsation of the motor, solving the problem of large cogging torque and large torque pulsation. In other words, this invention effectively weakens cogging torque and torque pulsation through the process groove at the yoke connection, and also effectively prevents magnetic saturation. The straight-bar stator of this invention forms a ring-shaped stator lamination structure by connecting multiple first stator lamination units end to end, and then stacks and presses these multiple ring-shaped stator lamination structures into a single stator core structure.

[0065] The inventive point of this invention:

[0066] 1. The outer surface of the yoke of the straight stator lamination is a straight surface, and each group of stator laminations can be laid out in close contact without any overlap, thus improving material utilization. The inner diameter surface of the straight stator lamination and the inner surface of the yoke can be laid out in close contact without any overlap between the two rows of stator laminations, thus improving material utilization.

[0067] 2. A first process groove is provided at the junction of the inner diameter surface of the stator lamination and the yoke. The width of the first process groove satisfies the following formula: b3=2*(hj2-h1+h2)*tan(180° / Z1)+(0.2~0.5)mm. The depth of the second process groove on the inner diameter surface is t1=0.1~0.3mm, which can effectively reduce the cogging torque and torque pulsation of the motor and avoid secondary processing.

[0068] 3. A boss is designed on the inner surface of the yoke. The height of the boss h2 must be greater than the process chamfer radius. The chamfer is left on the boss to prevent long and thin material from being left on both sides of the pole shoe after the stator lamination is stamped, thus avoiding secondary processing.

[0069] 4. The straight bar stator core has matching arc protrusions and arc grooves at the joints on both sides. The width of the arc protrusions satisfies the relationship: b4=(20%~40%)*(hj2+h2) / tan(180° / Z1), which can effectively prevent cracking of the straight bar stator core after it is rounded.

[0070] 5. The yoke portion above the arc protrusion is offset in the opposite direction of the arc protrusion, and the yoke portion above the arc groove is offset towards the groove opening of the arc groove. The two offset angles are the same. After offset, the yoke portion above the arc groove has an overlap protruding structure. The yoke portion above the arc protrusion is designed with a sharp corner protrusion, so that this part of the yoke also has an overlap protruding structure. The two protruding structures have the same height. The offset angle a and the protrusion height h3 satisfy the relationship: h3=0.2~0.5mm=R / cos(a+180° / Z1)-R / cos(180° / Z1). The overlap protruding structure is beneficial to the welding process.

[0071] 6. The stator lamination teeth have pre-reserved grooves on both sides of the snap-in point position. The depth of the pre-reserved grooves satisfies the following relationship:

[0072] t2 = (1% ~ 2%) * bt / 2, which ensures that the tooth width dimension does not exceed the tolerance range after stamping and fastening.

[0073] This invention solves the following technical problem:

[0074] 1. This solves the problem of low material utilization caused by the need to reserve overlap when laying out stator laminations;

[0075] 2. Solved the problem of damage to cutting tools and laminations during stator lamination stamping;

[0076] 3. This solved the problem of excess material remaining at the edges and corners after stator lamination stamping, requiring secondary processing;

[0077] 4. Solved the problems of large cogging torque and large torque ripple in the motor;

[0078] 5. Solved the problem of low stator roundness caused by cracking after the stator core is rounded;

[0079] 6. It solved the problem of numerous welding processes and low production efficiency after the stator core is formed into a circle;

[0080] 7. Solved the problem of increased stator tooth width caused by stamping and fastening points on stator laminations;

[0081] 8. This solved the problem of excessively wide slots after the stator core was rounded, which led to reduced motor performance.

[0082] To address the issues in the technical background, this invention proposes a straight bar stator core with high material utilization and high rounding accuracy, without overlapping edges. The specific technical solution is as follows:

[0083] 1. The straight stator core without overlapping edges of the present invention is formed by stacking multiple stator laminations, each stator lamination comprising multiple stator units connected in sequence, each stator unit comprising a yoke, a toothed portion and a pole shoe.

[0084] 2. For example Figure 2 As shown, the inner diameter surface of the straight stator lamination and the inner surface of the yoke can be fitted together for interlocking and arrangement, and no overlap is required between the two rows of stator laminations; the outer surface of the yoke of the straight stator lamination is a straight surface, and each group of stator laminations can be fitted together for arrangement, and no overlap is required between them. Eliminating the two overlaps can greatly shorten the arrangement material length and improve the material utilization rate of the stator laminations.

[0085] In some embodiments, a third stator lamination unit 103 is also included, wherein the third stator lamination unit 103, the first stator lamination unit 101, and the second stator lamination unit 102 are connected in sequence.

[0086] The third stator lamination unit 103 includes a third stator tooth 5 and a third stator yoke 6. One end of the third stator tooth 5 is connected to the third stator yoke 6, and the other end extends toward the first stator yoke 2 and is connected to the first stator yoke 2. The first stator tooth 1 extends toward the third stator yoke 6 and is connected to the third stator yoke 6.

[0087] The third stator yoke 6 is configured such that the end face of the third stator tooth 5 is the fifth end face 61, and the end face opposite to the third stator tooth 5 is the sixth end face 62; the free end face of the first stator tooth 1 is adapted to and fits against the fifth end face 61, and the free end face of the third stator tooth 5 is adapted to and fits against the first end face 21.

[0088] The present invention further adapts and fits the free end face of the first stator tooth of the first stator lamination unit with the fifth end of the third stator yoke of the third stator lamination unit, and the free end face of the third stator tooth with the first end of the first stator yoke, thereby effectively eliminating the pre-reserved overlap bf1 between the two rows of stator laminations in the original set, which can further improve the utilization rate of materials. That is, the inner diameter surface of the straight stator lamination of the present invention fits with the inner surface of the yoke for layout, and no pre-reserved overlap is required between the two rows of stator laminations, which further improves the utilization rate of materials and further reduces the cost of stator.

[0089] In some embodiments, there are multiple second stator lamination units 102, which are connected sequentially; there are multiple third stator lamination units 103, which are connected sequentially; the first stator tooth 1 is inserted between two adjacent third stator teeth 5, and the third stator tooth 5 is inserted between two adjacent first stator teeth 1, forming an interlocking arrangement structure. This is a preferred structural form of the second and third stator lamination units of the present invention, that is, multiple stator lamination units can be manufactured simultaneously in a row of laminations, forming a ring-shaped stator lamination structure that can be pressed into a stator core structure. Since the first overlap bf1 reserved between two rows of stator laminations in a set and the second overlap bf2 between each set of stator laminations are effectively eliminated, the utilization rate of materials can be effectively improved and the cost of the stator can be reduced.

[0090] In some embodiments, the free end face of the first stator tooth 1 is a first arc-shaped surface, the fifth end face 61 of the third stator yoke 6 is a second arc-shaped surface, and the first arc-shaped surface and the second arc-shaped surface are in close contact; the free end face of the third stator tooth 5 is a third arc-shaped surface, and the first end face 21 of the first stator yoke 2 is a fourth arc-shaped surface, and the third arc-shaped surface and the fourth arc-shaped surface are in close contact;

[0091] During the fabrication of the layout, the second end face 22 of the first stator yoke 2 is a straight plane, and the fourth end face 42 of the second stator yoke 4 is a straight plane.

[0092] This is a preferred structural form of the free end face and the fifth end face of the first stator tooth of the present invention. The arc-shaped surface structure forms an arc-shaped surface fit, and the straight plane can form a planar fit. Both can effectively eliminate the original overlap, save materials, improve material utilization, and reduce the cost of the stator.

[0093] In some embodiments, the first arc surface is a concave arc surface, the second arc surface is a convex arc surface, the third arc surface is a concave arc surface, and the fourth arc surface is a convex arc surface. This is a preferred structural form of the first, second, third, and fourth arc surfaces of the present invention, which can form an arc surface structure with concave and convex fit.

[0094] In some embodiments, the connecting groove 9 is opposite to the second end face 22 and the minimum distance between the groove and the second end face 22 is the yoke connection height h1; the width of the first process groove 7 is b3, the distance between the first end face 21 and the contact position of the inner surface boss 8 of the yoke and the second end face 22 is the yoke height hj2, and the number of teeth of the first stator tooth 1 is the number of stator core teeth Z1. The above parameters satisfy the following relationship: b3=2*(hj2-h1+h2)*tan(180° / Z1)+(0.2~0.5)mm.

[0095] like Figure 4 As shown, a first process groove is provided at the junction of the inner diameter surface and the yoke of the stator lamination. The width of the first process groove satisfies the following formula: b3=2*(hj2-h1+h2)*tan(180° / Z1)+(0.2~0.5)mm. Part of the process groove depth is on the inner diameter surface, and the other part is at the yoke junction. The depth of the second process groove on the inner diameter surface is t1=0.1~0.3mm. The process groove effectively reduces the cogging torque and torque pulsation of the motor; during the stamping process, the process groove allows the machine oil to better penetrate into the lamination material, increasing lubrication and buffering effects, and preventing damage to the cutting tools and laminations; Figure 6 As shown, the process groove can prevent long, thin pieces of material from remaining at the joint of the yoke, thus avoiding secondary processing.

[0096] In some embodiments, the depth t1 of the second process groove is 0.2–0.3 mm; a process chamfer is provided at the junction of the first end face and the inner surface boss 8 of the yoke, and the h2 is greater than the radius of the process chamfer. For example... Figure 4 As shown, a boss is designed on the inner surface of the yoke of the stator lamination. The boss height h2 needs to be greater than the process chamfer radius, leaving the chamfer on the boss, as shown. Figure 6 As shown, the boss can prevent long, thin pieces of material from remaining on both sides of the pole shoe after the stator laminations are stamped, thus avoiding secondary processing.

[0097] In some embodiments, the tooth pitch between two adjacent first stator lamination units 101 is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth 1. In the annular stator lamination structure, along the radial direction, the distance between the second end face 22 and the center of the annular stator lamination structure is the stator radius R. The number of teeth of the first stator teeth 1 is the number of stator core teeth Z1. The above parameters satisfy the following relationship: L3=2*(R-h1)*tan(180° / Z1).

[0098] This invention achieves the following relationship through the tooth pitch of adjacent stator units: L3=2*(R-h1-t3)*tan(180° / Z1). The smaller the tooth pitch, that is, the shorter the length of the straight stator lamination, the shorter the sample width L2, thereby shortening the sample width of the stator lamination and improving the material utilization rate.

[0099] In some embodiments, the layout width of the straight stator lamination is L2, where L2 is the length of the plurality of first stator lamination units 101 connected sequentially, the number of teeth of the first stator tooth 1 is the number of teeth of the stator core Z1, and the tooth pitch between two adjacent first stator lamination units 101 is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth 1. The above parameters satisfy the following relationship:

[0100] L2 = (Z1 + 0.5) * L3 + (6 ~ 9 mm);

[0101] like Figure 2 As shown, the tooth pitch of the adjacent stator units satisfies the following relationship:

[0102] L3=2*(R-h1)*tan(180° / Z1), the width of the straight stator lamination sample satisfies the following relationship:

[0103] L2 = (Z1 + 0.5) * L3 + (6 ~ 9 mm), where R is the outer radius of the stator core and Z1 is the number of teeth in the stator core. The inner diameter surface of the straight stator lamination and the inner surface of the yoke can be fitted together for interlocking and arrangement, and no overlap is required between the two rows of stator laminations; the outer surface of the yoke of the straight stator lamination is a straight surface, and each group of stator laminations can be fitted together for arrangement, and no overlap is required between them. Eliminating two overlaps can greatly shorten the arrangement material length and improve the material utilization rate of the stator laminations. The material utilization rate of a row of stator laminations = V2 * 2 / L2 / (b2 + hj2 + h2), where V2 is the usable area of ​​the stator lamination.

[0104] The material utilization rate of the stator laminations in the nesting area is η, and the usable area of ​​the stator laminations in the nesting area is V2. Along the centerline direction of the first stator tooth 1, the maximum distance between the second end face 22 of the first stator yoke 2 and the free end face of the first stator tooth 1 is the width b2 of the stator core. The distance between the first end face 21 and the second end face 22 of the first stator yoke 2 is the height hj2 of the yoke. The above parameters satisfy the following relationship: η=V2*2 / (L2*(b2+hj2+h2).

[0105] In some embodiments, a first protrusion 11 is provided on the first stator yoke 2 of the first stator lamination unit at the beginning, protruding toward the first stator yoke 2 of the first stator lamination at the end, and a first groove 12 is provided on the first stator yoke 2 of the first stator lamination unit at the end, in a direction away from the first stator yoke 2 of the first stator lamination at the beginning. The first protrusion 11 can be inserted into the first groove 12 to form a snap-fit.

[0106] This invention effectively prevents cracking of the straight stator core after it is rounded by providing matching arc-shaped protrusions and grooves at the joints on both sides. (Existing structures do not use a protrusion and groove combination, resulting in a straight-line crack that is prone to breakage under welding stress; the protrusion and groove combination of this invention can form an offset angle during the stamping process, so the crack is not a straight line and is therefore less prone to cracking), ensuring the rounding accuracy of the stator core. (The joint in this invention refers to the crack between the first and last yokes after the straight stator core is rounded).

[0107] In some embodiments, the first protrusion 11 is an arc-shaped protrusion, the first groove 12 is an arc-shaped groove, the width of the arc-shaped protrusion along the direction perpendicular to the first end face 21 is b4, the distance between the first end face 21 and the second end face 22 of the first stator yoke 2 is the yoke height hj2, and the number of teeth of the first stator tooth 1 is the number of stator core teeth Z1. The above parameters satisfy the following relationship:

[0108] b4 = (20% ~ 40%) * (hj2 + h2) / tan(180° / Z1). For example... Figure 4 As shown, the stator core has matching arc protrusions and arc grooves at the joints on both sides. The width of the arc protrusions satisfies the following relationship:

[0109] b4 = (20% ~ 40%) * (hj2 + h2) / tan(180° / Z1). Satisfying the above relationship ensures that after the straight bar stator core is rounded, the arc protrusion and arc groove are tightly combined, increasing the bonding strength. This effectively avoids cracking after the straight bar stator core is rounded, and increases the rounding accuracy of the stator core.

[0110] In some embodiments, a second protrusion 13 is provided on the second end face 22 of the first stator yoke 2 of the first stator lamination unit at the beginning, protruding in a direction away from the first end face 21. A third protrusion 14 is provided on the second end face 22 of the first stator yoke 2 of the first stator lamination unit at the end, protruding in a direction away from the first end face 21. The first contact surface 15 is formed between the first protrusion 11 and the first groove 12 and the first end face 21, and the two first stator yokes 2 are opposite to each other and in contact. The side of the second protrusion 13 is in contact with the side of the third protrusion 14 to form a second contact surface 16. The second contact surface 16 and the first contact surface 15 are located on different surfaces. The second contact surface 16 is closer to the first stator tooth 1 at the beginning relative to the first contact surface 15. The second protrusion 13 is a sharp-angled protrusion. The third protrusion 14 is a protrusion formed smoothly on the second end face 22. The first process groove 7 is located radially inside the first contact surface 15.

[0111] After the stator core is formed into a circle, there is a protruding structure outside the joint. This is beneficial to the welding process, and the welding process only has one step, resulting in high production efficiency. The part of the yoke above the arc protrusion is offset in the opposite direction of the arc protrusion, and the part of the yoke above the arc groove is offset in the groove opening of the arc groove. The two offset angles are consistent. After offset, the yoke above the arc groove has a protruding structure outside the joint. The yoke above the arc protrusion is designed with a sharp corner protrusion, so that this part of the yoke also has a protruding structure outside the joint. The two protruding structures are the same height. By forming an offset angle, the crack during the manufacturing process is not a straight line, so it is not easy to crack, thus ensuring the stability of the stator core manufacturing performance.

[0112] In some embodiments, the first contact surface 15 and the second contact surface 16 both pass through the center of the annular stator lamination structure, and the included angle between their centers is α; the protrusion height of the second protrusion 13 is the same as the protrusion height of the third protrusion 14, both being h3, and h3 = 0.2~0.5mm = R / cos(α+180° / Z1)-R / cos(180° / Z1), where R is the distance between the second end face 22 and the center, which is the stator radius. Both yoke portions of the present invention have overlapping outward protrusion structures, and the two protrusion structures have the same height. These overlapping outward protrusion structures are beneficial for the welding process.

[0113] In some embodiments, the first stator tooth 1 includes a stator tooth body 17 and a pole shoe 18. One end of the pole shoe 18 is connected to the circumferential side of the stator tooth body 17 and is located at the position furthest from the first stator yoke 2. The other end extends in the circumferential direction. There are two pole shoes 18, which are arranged one-to-one with the circumferential sides of the stator tooth body 17.

[0114] A first snap point 191 protrudes from the end face of the stator tooth body 17. A pre-reserved groove 20 is provided on both sides of the first snap point 191, with a depth of t2. A second snap point 192 protrudes from the end face of the first stator yoke 2. The pre-reserved grooves on both sides of the snap point position on the stator lamination teeth ensure that the tooth width does not exceed the tolerance range after the snap points are stamped, thus improving the product qualification rate. (Snap points are structures that interlock between laminations to achieve positioning and connection between laminations, assembling them into a stator core.) During the stamping of snap points, the adjacent material is squeezed, increasing the size. Since the tooth width is a relatively important dimension, it is necessary to cut out the pre-reserved grooves.

[0115] In some embodiments, the circumferential width of the stator tooth body is the tooth width bt, and satisfies the relationship: t2 = (1%~2%) * bt / 2. Reserved grooves are provided on both sides of the snap-in point position of the stator lamination tooth. The depth of the reserved grooves satisfies the above relationship, ensuring that the tooth width dimension does not exceed the tolerance range after the snap-in point is stamped, allowing the subsequent frame to be smoothly fitted onto the stator core.

[0116] In some embodiments, after forming the annular stator lamination structure, the first stator tooth 1 is located radially inside the first stator yoke 2, i.e., the stator core for an inner rotor motor. With the stator core teeth inside the yoke, i.e., the stator core for an inner rotor motor, the straight stator core is rounded to ensure that the slot width is not too large, thus improving motor performance.

[0117] The present invention also provides a stator comprising the straight stator laminations described in the preceding claim.

[0118] The beneficial effects of the stator of the present invention are as follows:

[0119] 1. The outer surface of the yoke of the straight stator lamination is a straight surface. When laying out the laminations, there is no need to leave an overlap between each group of stator laminations, which improves material utilization and reduces stator cost.

[0120] 2. The inner diameter surface of the straight stator lamination of the present invention can be fitted with the inner surface of the yoke for layout, and no overlap is required between the two rows of stator laminations, which improves material utilization and reduces stator cost;

[0121] 3. A process groove is provided at the junction of the inner diameter surface of the stator lamination and the yoke. During the stamping process, the machine oil can better penetrate into the lamination material, preventing damage to the cutting tools and laminations. The process groove can also prevent long and thin excess material from remaining at the corners of the stator lamination after stamping, avoiding secondary processing. The process groove also has the effect of reducing the cogging torque and torque pulsation of the motor.

[0122] 4. The straight bar stator core has matching arc protrusions and arc grooves at the joints on both sides, which can effectively prevent the straight bar stator core from cracking after it is rounded (the protrusions and grooves of this invention can form an offset angle during the stamping process, so the crack is not a straight line, so it is not easy to crack), thus ensuring the rounding accuracy of the stator core.

[0123] 5. After the stator core is formed into a circle, there is a protruding structure on the outside of the joint, which is beneficial to the welding process. Moreover, the welding process only has one step, resulting in high production efficiency.

[0124] 6. The stator lamination teeth have reserved grooves on both sides of the snap point position to ensure that the tooth width dimension does not exceed the tolerance range after the snap point is stamped, thereby improving the product qualification rate.

[0125] 7. The stator core teeth are located inside the yoke, i.e., the stator core for an internal rotor motor. After the straight stator core is rounded, the slot width is ensured to be not too large, thus improving the performance of the motor.

[0126] The present invention also provides an electric motor comprising the aforementioned stator.

[0127] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A straight stator lamination, characterized in that: include: The straight stator lamination is fabricated simultaneously during the layout process, with multiple stator lamination units having the same structure. The multiple stator lamination units include a first stator lamination unit (101) and a second stator lamination unit (102). The first stator lamination unit (101) includes a first stator tooth (1) and a first stator yoke (2). One end of the first stator tooth (1) is connected to the first stator yoke (2), and the other end extends in a direction away from the second stator lamination unit (102). The second stator lamination unit (102) includes a second stator tooth (3) and a second stator yoke (4). One end of the second stator tooth (3) is connected to the second stator yoke (4), and the other end extends in a direction away from the first stator lamination unit (101). The first stator yoke (2) and the second stator yoke (4) are connected to each other. The first stator yoke (2) is configured such that the end face of the first stator tooth (1) is the first end face (21), and the end face opposite to the first stator tooth (1) is the second end face (22); the second stator yoke (4) is configured such that the end face of the second stator tooth (3) is the third end face (41), and the end face opposite to the second stator tooth (3) is the fourth end face (42); the second end face (22) and the fourth end face (42) are adapted to each other and are fitted together. The first stator lamination unit (101) is multiple, and the multiple first stator lamination units are connected in sequence to form the straight stator lamination, and the first stator lamination unit at the beginning end is connected to the first stator lamination unit at the end end to form a ring stator lamination structure. The first stator yoke (2) has an inner surface boss (8) protruding outward on the first end face (21), and the height of the inner surface boss (8) from the first end face (21) is the height h2 of the inner surface boss. The inner surface bosses (8) of the two adjacent first stator yokes (2) are provided with connecting grooves (9) at the joint, and a sink groove is also provided at the top of the connecting groove (9) to form a first process groove (7).

2. The straight stator lamination according to claim 1, characterized in that: It also includes a third stator lamination unit (103), wherein the third stator lamination unit (103), the first stator lamination unit (101) and the second stator lamination unit (102) are connected in sequence; The third stator lamination unit (103) includes a third stator tooth (5) and a third stator yoke (6). One end of the third stator tooth (5) is connected to the third stator yoke (6), and the other end extends toward the first stator yoke (2) and is connected to the first stator yoke (2). The first stator tooth (1) extends toward the third stator yoke (6) and is connected to the third stator yoke (6). The third stator yoke (6) is configured such that the end face of the third stator tooth (5) is the fifth end face (61), and the end face opposite to the third stator tooth (5) is the sixth end face (62); the free end face of the first stator tooth (1) is adapted to and fits against the fifth end face (61), and the free end face of the third stator tooth (5) is adapted to and fits against the first end face (21).

3. The straight stator lamination according to claim 2, characterized in that: There are multiple second stator lamination units (102), and multiple second stator lamination units are connected in sequence; there are multiple third stator lamination units (103), and multiple third stator lamination units are connected in sequence; the first stator tooth (1) is inserted between two adjacent third stator teeth (5), and the third stator tooth (5) is inserted between two adjacent first stator teeth (1), forming an interlocking arrangement structure.

4. The straight stator lamination according to claim 2, characterized in that: The free end face of the first stator tooth (1) is a first arc-shaped surface, and the fifth end face (61) of the third stator yoke (6) is a second arc-shaped surface. The first arc-shaped surface and the second arc-shaped surface are in contact. The free end face of the third stator tooth (5) is a third arc-shaped surface, and the first end face (21) of the first stator yoke (2) is a fourth arc-shaped surface. The third arc-shaped surface and the fourth arc-shaped surface are in contact.

5. The straight stator lamination according to claim 4, characterized in that: The first arc surface is a concave arc surface, the second arc surface is a convex arc surface; the third arc surface is a concave arc surface, and the fourth arc surface is a convex arc surface.

6. The straight stator lamination according to claim 1, characterized in that: During the fabrication of the layout, the second end face (22) of the first stator yoke (2) is a straight plane, and the fourth end face (42) of the second stator yoke (4) is a straight plane.

7. The straight stator lamination according to claim 1, characterized in that: The minimum distance between the connecting groove (9) and the second end face (22) is the yoke connection height h1; the width of the first process groove (7) is b3; the distance between the first end face (21) and the contact position of the inner surface boss (8) of the yoke and the second end face (22) is the yoke height hj2; the number of teeth of the first stator tooth (1) is the number of stator core teeth Z1; the above parameters satisfy the following relationship: b3=2 (hj2-h1+h2) tan(180° / Z1)+(0.2~0.5)mm.

8. The straight stator lamination according to claim 1, characterized in that: A second process groove (10) is provided on the free end face of the first stator tooth (1), and the depth of the second process groove (10) is t1=0.2~0.3mm; a process chamfer is provided at the contact position between the first end face and the inner surface boss (8) of the yoke, and the h2 is greater than the radius of the process chamfer.

9. The straight stator lamination according to claim 7, characterized in that: The tooth pitch between two adjacent first stator lamination units (101) is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth (1). In the annular stator lamination structure, along the radial direction, the distance between the second end face (22) and the center of the circle is the stator radius R. The number of teeth of the first stator teeth (1) is the number of stator core teeth Z1. The above parameters satisfy the following relationship: L3=2 (R-h1) tan(180° / Z1).

10. The straight stator lamination according to claim 9, characterized in that: The layout width of the straight stator lamination is L2, where L2 is the length of the first stator lamination units (101) connected sequentially. The number of teeth of the first stator tooth (1) is the number of teeth of the stator core Z1. The tooth pitch between two adjacent first stator lamination units (101) is L3, where L3 is the distance between the centerlines of two adjacent first stator teeth (1). The above parameters satisfy the following relationship: L2 = (Z1 + 0.5) L3+ (6~9mm).

11. The straight stator lamination according to claim 1, characterized in that: A first protrusion (11) is provided on the first stator yoke (2) of the first stator lamination unit at the beginning of the first stator lamination unit, which protrudes in the direction of the first stator yoke (2) of the first stator lamination unit at the end of the first stator lamination unit, and a first groove (12) is provided on the first stator yoke (2) of the first stator lamination unit at the end of the first stator lamination unit, which is away from the first stator yoke (2) of the first stator lamination unit at the beginning of the first stator lamination unit. The first protrusion (11) can be inserted into the first groove (12) to form a snap-fit.

12. The straight stator lamination according to claim 11, characterized in that: The first protrusion (11) is an arc protrusion, the first groove (12) is an arc groove, the width of the arc protrusion along the direction perpendicular to the first end face (21) is b4, the distance between the first end face (21) and the second end face (22) of the first stator yoke (2) is the yoke height hj2, and the number of teeth of the first stator tooth (1) is the number of stator core teeth Z1. The above parameters satisfy the following relationship: b4 = (20%~40%) (hj2+h2) / tan(180° / Z1).

13. The straight stator lamination according to claim 11, characterized in that: A second protrusion (13) is provided on the second end face (22) of the first stator lamination unit at the first end, protruding away from the first end face (21). A third protrusion (14) is provided on the second end face (22) of the first stator lamination unit at the end, protruding away from the first end face (21). The first contact surface is located between the first protrusion (11) and the first groove (12) and the first end face (21), and the two first stator lamination units (2) are opposite to each other and in contact. 15); the side of the second protrusion (13) is connected to the side of the third protrusion (14) to form a second contact surface (16), and the second contact surface (16) and the first contact surface (15) are located on different surfaces. The second contact surface (16) is closer to the first stator tooth (1) at the head end relative to the first contact surface (15). The second protrusion (13) is a sharp protrusion, and the third protrusion (14) is a protrusion formed smoothly on the second end face (22). The first process groove (7) is located radially inside the first contact surface (15).

14. The straight stator lamination according to claim 13, characterized in that: The first contact surface (15) and the second contact surface (16) both pass through the center of the annular stator lamination structure, and the included angle between the two centers is a; the protrusion height of the second protrusion (13) is the same as the protrusion height of the third protrusion (14), both being h3, and h3 = 0.2~0.5mm = R / cos(a+180° / Z1)-R / cos(180° / Z1), where R is the distance between the second end face (22) and the center, which is the stator radius.

15. The straight stator lamination according to any one of claims 1-14, characterized in that: The first stator tooth (1) includes a stator tooth body (17) and a pole shoe (18). One end of the pole shoe (18) is connected to the circumferential side of the stator tooth body (17) and is located furthest from the first stator yoke (2). The other end extends in the circumferential direction. There are two pole shoes (18), which are arranged one-to-one with the circumferential sides of the stator tooth body (17). The stator tooth body (17) has a first fastening point (191) protruding from its end face. Both sides of the first fastening point (191) are provided with reserved grooves (20). The depth of the reserved grooves (20) is t2. The first stator yoke (2) has a second fastening point (192) protruding from its end face.

16. The straight stator lamination according to claim 15, characterized in that: The circumferential width of the stator tooth body is the tooth width bt, and satisfies the relationship: t2=(1%~2%) bt / 2.

17. The straight stator lamination according to any one of claims 1-14, characterized in that: After forming the annular stator lamination structure, the first stator tooth (1) is located on the radial inner side of the first stator yoke (2), that is, the stator core for the inner rotor motor.

18. A stator, characterized in that: Includes the straight stator laminations as described in any one of claims 1-17.

19. An electric motor, characterized in that: Includes the stator as described in claim 18.

Images