A method for manufacturing a stator core by winding with a yoke reinforcement

Abstract

The present application relates to a manufacturing method of a stator core produced by winding with a yoke reinforcement, in which a steel strip is wound into a spirally stacked stator core, and in the punching stage, a connecting rib is reserved so that the two ends of the connecting rib are respectively connected to two adjacent tooth tips, so that the connecting rib provides a supporting force for the tooth tips during the winding process; when rolling inward: the connecting rib abuts against the tooth tips to provide a reverse supporting force, thereby reducing the pressure on the yoke, so that the yoke can be smoothly wound into a circle, and the yoke is prevented from being deformed or partially bent during the winding process; the present invention does not directly punch out into the shape of the final tooth portion, and after the steel strip is pressed into the final stator core preform, the connecting rib is punched and removed; this segmented punching method is conducive to the forming of the stator core, and can reduce the deformation or local bending of the steel strip during the winding process, thereby helping to improve the quality of the product, and also improves the overall production quality.

Description

Technical Field

[0001] The present application relates to the technical field of motor stator production, and in particular to a method for manufacturing a yoke-reinforced stator core by winding. Background Art

[0002] The traditional stator core production method usually winds the stamped strip into a spiral stator lamination. However, in the production process of the wound stator core, when the stamped strip is wound into a spiral stator lamination, the outer side of the steel strip yoke is stretched and the inner side of the yoke is compressed, causing elastic deformation. The inner and outer sides are subjected to stress in two different directions, which keeps the yoke width stable within the effective range.

[0003] When the yoke is small, during the stamping and winding process, it is easy to cause the steel strip to deform, the yoke to break after winding, and it is impossible to finalize the shape, and uneven lamination during the product lamination process. These problems can easily lead to product defects.

[0004] In order to solve the problem that the steel strip is easily deformed or partially bent or broken during the winding process, a new method for manufacturing a stator core by winding with a reinforced yoke is proposed. Summary of the invention

[0005] The purpose of the present invention is to overcome the technical problem in the prior art that when a steel strip with a smaller yoke is wound, the steel strip is easily deformed or partially bent or broken, and to provide a manufacturing method for a stator core produced by winding with a reinforced yoke.

[0006] A method for manufacturing a stator core with a yoke reinforcement by winding, comprising a motor core stator core made of steel strips and steel bands wound into a spiral stack, wherein the stator core comprises a yoke and a tooth portion, wherein the tooth portion is provided with tooth slots arranged at equal intervals. The method for manufacturing the stator core comprises the following steps:

[0007] Step 1: Uncoiling and cutting: Uncoiling the steel coil, cutting the raw material steel strip coil according to the set steel strip width requirements, and cutting the steel strip coil into several steel strips;

[0008] Step 2: Material sorting and leveling: The cut steel strip is put on the machine, and the steel strip is trimmed into a flat and uniform long strip through the unwinding machine, leveling machine and feeder. The raw material is a steel coil. By unwinding the raw material and leveling it with a leveling machine, a relatively flat steel plate can be obtained. The steel plate is cut to obtain a relatively flat steel strip;

[0009] Step 3. Stamping: Send the leveled steel strip to the guide plate at the feed port of the progressive die, so that the steel strip is gradually punched out with a center groove and buckle points according to the set step distance, and a continuous steel strip with a yoke, teeth and connecting ribs is formed by punching. The buckle point design can ensure a stable number of layers when punching the tooth shape to avoid stratification. After stamping through the die, the straight strip is divided into several unconnected, linear continuous toothed strips with exactly the same size. In the blanking stage, a connecting rib is reserved instead of directly punching into the final tooth shape. Punching and cutting the connecting rib in the final stage can reduce the bending or breaking of the steel strip during the intermediate processing and increase the success rate of the product;

[0010] Step 4, steel strip winding: Take the leveled steel strip, feed it into the winding mechanism, and wind it into a spiral loose semi-finished product with a predetermined number of turns. At this time, each connecting rib and the yoke are stretched or extruded at the same time, and then separated into a single spiral monomer. The connecting rib plays the role of sharing the pressure in this step. It can bear the extrusion and tension that the yoke originally borne alone, enhance the strength of the steel strip, and overcome the jitter and deformation generated during stamping and winding production. It is wound into a spiral loose semi-finished product with a predetermined number of turns, and then split into multiple spiral monomers, each of which is manufactured into a separate stator core;

[0011] Step 5: Connect and fix: Place the spiral monomer in the mold, align the buckle points of the adjacent upper layer with the buckle points of the lower layer and the center groove, press it by machine, and then connect the adjacent upper layer and lower layer to fix the spiral monomer into an integrated stator core preform. Connect by pressing, and use the adjacent buckle points to fix and connect the stator core preform into an integrated stator core preform;

[0012] Step 6: Shaping: Shaping the stator core preform so that the dimensions of each phase of the product meet the standard;

[0013] Step 7, Punching: Cut off the excess connecting ribs, fix the stator core preform on the punching device, use the punching device to punch from the outside of the stator core to the inside of the tooth slot, cut off the reserved connecting ribs, and get the final stator core. The connecting ribs have completed their functions and are in a bent state, so the connecting ribs are cut according to the final tooth shape so that the tooth tips of each tooth are separated from each other.

[0014] As a further improvement measure of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, the root of the tooth is connected to the yoke, and the two ends of each connecting rib are respectively connected to the tooth tips of two adjacent teeth.

[0015] As a further improvement measure of the present invention, in the manufacturing method of the above-mentioned yoke-reinforced winding stator core, in the step seven punching step, the punching device includes an abutment member arranged on the inner side of the tooth slot and a punch arranged on the outer side of the tooth slot, and the punching device is used to punch from the outer side of the stator core to the inner side of the tooth slot to cut off the reserved connecting ribs.

[0016] As a further improvement measure of the present invention, in the above-mentioned method for manufacturing a stator core by winding with yoke reinforcement, in the step five, the connection method also includes welding or riveting to fix the adjacent upper and lower layers.

[0017] As an embodiment of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, each buckle point is arranged in sequence with equal spacing along the length direction of the steel strip, and each buckle point makes the upper layer and the lower layer of each steel strip after winding and forming mutually fixed and clamped. In this way, after winding, the buckle points between the upper layer and the lower layer adjacent to each other can be fixed together.

[0018] As a further improvement measure of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, the buckle point includes a buckle point groove and a buckle point protrusion. In step seven, the buckle point protrusion of the upper layer is clamped in the buckle point groove of the lower layer to fix the upper layer and the lower layer. In this way, after the buckle point protrusion of the upper layer of the steel strip after winding and the adjacent buckle point groove of the lower layer are buckled with each other, the surface is flat without forming a protrusion, and a tightly stacked stator core is formed.

[0019] As a further improvement measure of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, each buckle point is set in the tooth part of the steel strip. The overall proportion of the tooth part is relatively large, and adding a buckle point does not affect the overall strength. The buckle point is rectangular or circular in shape.

[0020] As a further improvement measure of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, the two ends of each yoke are respectively connected to the tooth roots of two adjacent teeth, and the two ends of each connecting rib are respectively connected to the tooth tips of two adjacent teeth.

[0021] As a further improvement measure of the present invention, in the manufacturing method of the stator core produced by winding with yoke reinforcement, the width of each yoke is greater than the width of the connecting rib. The connecting rib is a supporting component in an intermediate transition stage. According to the shape of the tooth, a small section of thinner connecting rib is reserved to share the tension or pressure.

[0022] As an embodiment of the present invention, in the stator core, the tooth tip of the tooth portion faces the inside of the stator core, or the tooth tip of the tooth portion faces the outside of the stator core. This can be wound according to the winding requirements of the stator core.

[0023] The technical advantages of the present application are as follows: During the blanking stage, connecting ribs are reserved so that the two ends of the connecting ribs are respectively connected to two adjacent tooth tips. In this way, during the winding process, the connecting ribs provide a reverse force on the tooth tips. When rolling inward, the connecting ribs rest against the tooth tips, provide reverse support force, reduce the pressure on the yoke, and enable the yoke to be slowly wound up, preventing the yoke from breaking or bending due to excessive extrusion pressure. Similarly, when rolling outward, the connecting ribs provide tension to the tooth tips, pull the tooth tips on both sides, reduce the tensile force on the yoke, and enable the yoke to be smoothly wound up. The present invention does not directly cut into the shape of the final tooth portion, but waits until the steel strip is pressed into the final stator core preform before blanking and cutting the connecting ribs. This segmented blanking method improves the strength of the steel strip and reduces the possibility of deformation or local bending of the steel strip during the winding process, which is beneficial to improving the quality of the product and the overall production quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A preparation flow chart of a method for manufacturing a stator core by winding with yoke reinforcement provided in one embodiment of the present application.

[0025] Figure 2 A diagram of the structural changes of step one and step two in a manufacturing method provided in one embodiment of the present application.

[0026] Figure 3 A diagram of structural changes in step three of the manufacturing method provided in one embodiment of the present application.

[0027] Figure 4 A schematic cross-sectional view of a steel strip in step three of a manufacturing method provided in one embodiment of the present application.

[0028] Figure 5 This is a diagram showing the state changes of the steel strip in step 4 of the manufacturing method provided in one embodiment of the present application.

[0029] Figure 6 This is a three-dimensional diagram of the spiral monomer in step 4 of the manufacturing method provided in one embodiment of the present application.

[0030] Figure 7 A top view of a stator core preform in step five of a manufacturing method provided in an embodiment of the present application.

[0031] Figure 8 A top view of the final stator core in step seven of the manufacturing method provided in one embodiment of the present application.

[0032] Fig. 9 A schematic diagram of the cutting principle in step seven provided in an embodiment of the present application.

[0033] Fig.10 Provided for an embodiment of the present application Fig. 9 A magnified view of some of the structures in .

[0034] Fig.11 A schematic diagram of a winding process with the tooth tips facing outwards is provided for another embodiment of the present application.

[0035] Figure numerals: 1-steel strip; 10-tooth groove; 11-upper layer; 12-lower layer; 2-stator core, 20-center slot, 3-yoke; 4-tooth portion: 41-tooth root portion, 42-tooth tip portion; 5-buckle point; 50-buckle point slot; 51-buckle point protrusion; 6-connecting rib. DETAILED DESCRIPTION

[0036] In order to more clearly illustrate the overall concept of the present invention, a detailed description is given below in an exemplary manner in conjunction with the accompanying drawings.

[0037] It should be noted that many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. However, if it is indicated as a direct connection, it means that the two connected bodies are not connected through an intermediate structure, but are only connected to form a whole through a connecting structure. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0039] As shown in FIG. 1 to FIG. 11 , the present application provides a method for manufacturing a stator core by winding with a yoke reinforcement.

[0040] As shown in Figures 1 to 10, in an embodiment of the present application, a method for manufacturing a stator core with a yoke-reinforced winding is provided, wherein a steel strip 1 is wound into a spirally stacked stator core 2, wherein the stator core includes a yoke 3 and a tooth portion 4, and the tooth portion 4 is provided with tooth slots 10 arranged at equal intervals.

[0041] The present invention provides a method for manufacturing a stator core of a motor core with a yoke-enhanced winding process, which comprises the following steps.

[0042] As shown in Figure 2: Step 1, unwinding and cutting: unwind the steel coil, cut the raw material steel strip coil according to the width requirement of the stator core 2, and cut the steel strip coil into several long strips of steel strips 1; the present invention uses a whole steel strip 1, which is directly wound into a stator core 2. The raw material is a steel coil, and the raw material is unwinded and the steel plate is divided to obtain a relatively flat steel strip 1. That is, the length of each steel strip 1 is the product of the number of winding layers and the circumference of the stator core 2. Each steel strip 1 is leveled by a leveling machine, and the length of each steel strip 1 can be completely wound into a stator core 2.

[0043] As shown in Figure 2: Step 2, material sorting and leveling: After each steel strip 1 is cut into equal lengths and widths, each steel strip 1 is sorted. Leveling by a leveling machine can obtain a relatively flat steel strip 1, so that each steel strip 1 is stacked in sequence, and the edges of each steel strip 1 are relatively aligned, and then accurately positioned through the feed backing and guide pins. The neat material strips after material sorting are conducive to improving the accuracy of later processing and reducing product quality problems.

[0044] As shown in Figures 3 and 6: Step 3, stamping, the leveled steel strip 1 is sent to the guide plate of the mold feed inlet, so that the steel strip 1 is gradually punched out with a center groove and buckle points according to the set step distance, and a continuous steel strip with a yoke, a tooth part and a connecting rib is formed by stamping.

[0045] Specifically, if Figure 4 As shown: each buckle point 5 is arranged in equal intervals along the length direction of the steel strip 1, and each buckle point 5 makes the upper layer 11 and the lower layer 12 of each steel strip 1 fixedly connected to each other after winding. The buckle point 5 includes a buckle point groove 50 and a buckle point protrusion 51. In the step 7, the buckle point protrusion 51 of the upper layer 11 is clamped in the buckle point groove 50 of the lower layer 12, so that the upper layer 11 and the lower layer 12 are fixed. Each of the buckle points 5 is arranged in the tooth portion 4 of the steel strip 1, and the buckle point 5 is rectangular or circular in shape, and a rectangular shape is used in the present invention.

[0046] The buckle points 5 are evenly distributed along the length direction of the steel strip 1, and the intervals between the buckle points 5 are the same as the intervals between the center lines of the tooth profiles. The design of the buckle points 5 can ensure that a stable number of layers is maintained when punching the tooth profile, avoiding the occurrence of delamination.

[0047] like Figure 3 As shown: Punching the center groove: The steel strip 1 is punched synchronously using a progressive die, and the center groove 20, the yoke 3, the tooth 4 and the connecting rib 6 are punched out in the center of the steel strip 1 in sequence and at equal intervals. After being punched by the die, the straight strip is divided into a number of continuous toothed strips that are not connected to each other and have completely consistent dimensions and are linear. In the punching stage, a connecting rib 6 is reserved when manufacturing the center groove 20, so that the two ends of the connecting rib 6 are respectively connected to two adjacent tooth tips 42.

[0048] During the punching stage, a connecting rib 6 is reserved so that two ends of the connecting rib 6 are respectively connected to two adjacent tooth tips 42 , so that during the winding process, the connecting rib 6 provides a reverse force on the tooth tips 42 .

[0049] like Figure 5 As shown, the two ends of each yoke 3 are respectively connected to the tooth root 41 of two adjacent teeth 4, and the two ends of each connecting rib 6 are respectively connected to the tooth tip 42 of two adjacent teeth 4. The width of each yoke 3 is greater than the width of the connecting rib 6. The connecting rib 6 plays a role in sharing pressure and tension, and its width is smaller than that of the yoke 3, so it will be deformed first, but will not affect the yoke 3.

[0050] An embodiment of the present invention in which the tooth tip 42 of the tooth portion 4 faces the inner side of the stator core 2. That is, when rolling inward: the connecting rib 6 abuts against the tooth tip 42 to provide a reverse support force, reducing the pressure on the yoke 3, so that the yoke 3 can be slowly wound, preventing the yoke 3 from breaking or bending due to excessive extrusion pressure.

[0051] The present invention does not directly cut into the shape of the final tooth portion 4, but waits until the steel strip 1 is pressed into the final stator core preform before punching and cutting the connecting rib 6. The segmented punching increases the strength of the steel strip 1, reduces the bending or breaking of the steel strip 1 during the intermediate processing, increases the success rate of the product, reduces the loss caused by bending and breaking, and also improves the overall production quality.

[0052] From the strip material to the spirally wound material strip, the connecting rib 6 can share the extrusion and tension originally borne by the yoke 3 alone, so that the strength of the steel strip 1 is increased, and the deformation caused by shaking during stamping and winding production can be overcome. In this way, the material strip can be smoothly formed from stamping to winding without twisting, deformation, etc., and the design of the connecting rib 6 will not affect the winding forming process.

[0053] like Figure 5-Figure 6 As shown: Step 4, steel strip winding: Take the steel strip 1 that has passed through the punched center groove, feed it into the winding mechanism, and wind it into a spiral loose semi-finished product with a predetermined number of turns. Each connecting rib 6 and the yoke 3 are stretched or squeezed at the same time, and each connecting rib 6 is bent or stretched under force, and then separated into a single spiral monomer. The connecting rib plays the role of sharing the pressure in this step, and can bear the extrusion and tension that the yoke 3 originally borne alone, so that the strength of the steel strip 1 is increased, and it can overcome the shaking deformation caused by the stamping and winding production, and is wound into a spiral loose semi-finished product with a predetermined number of turns, and then split into multiple spiral monomers, each of which is manufactured into a separate stator core 2.

[0054] like Figure 7As shown: Step 5, connection and fixation: Place the spiral monomer in the mold, align the adjacent buckle points 5 of the upper layer 11 and the buckle points 5 of the lower layer 12 and the center groove 20, and through compression, fix the steel strips using adjacent buckle points to form an integrated stator core preform.

[0055] Step 6: Shaping: Shape the stator core preform so that all dimensions of the product meet the standards.

[0056] like Figure 8-Figure 10 As shown: in step seven of the present invention, the redundant connecting ribs are cut off, the stator core preform is fixed on the punching device, and the bent connecting ribs 6 in the stator core preform are punched out to obtain the final stator core 2.

[0057] like Figure 8 As shown, in the stator core preform after winding, the connection rib 6 has been bent due to stress, and this part is no longer needed. The connection rib 6 in the stator core preform is cut laterally by a punching device. The punching device includes a support member arranged on the inner side of the tooth slot and a punch arranged on the outer side of the tooth slot. The punching device is used to punch from the outer side of the stator core to the inner side of the tooth slot to cut off the reserved connection rib 6.

[0058] like Figure 9-10 As shown, under the action of the cutting knife, all the connecting ribs 6 on each layer in the entire stator core preform are cut off at one time, so that the central groove 20 becomes the tooth groove 10.

[0059] As another winding method, the tooth tip 42 of the tooth portion 4 may be directed toward the outside of the stator core 2 according to design requirements.

[0060] like Fig.11 As shown, when the stator core is wound with the tooth tips facing outward, i.e., outwardly wound, the connecting ribs 6 provide tension to the tooth tips 42, pulling the tooth tips 42 on both sides, reducing the tensile force on the yoke 3, so that the yoke 3 can be slowly wound.

[0061] In the present application, during the punching stage, a connecting rib is reserved so that its two ends are respectively connected to two adjacent tooth tips, so that during the winding process, the connecting rib provides a reverse force on the tooth tip. When rolling inward: the connecting rib rests on the tooth tip, providing a reverse support force, reducing the pressure on the yoke, so that the yoke can be slowly wound up, and preventing the yoke from breaking or bending due to excessive extrusion pressure. When rolling outward, the connecting rib provides a pulling force on the tooth tip, pulling the tooth tips on both sides, reducing the tensile force on the yoke, and allowing the yoke to be smoothly wound up. The present invention does not directly punch out into the shape of the final tooth portion, and after the steel strip is pressed into the final stator core preform, the connecting rib is punched and removed. This segmented punching method improves the strength of the steel strip, reduces the bending or breaking of the steel strip during intermediate processing, improves the success rate of the product, reduces the losses caused by bending and breaking, and also improves the overall production quality.

[0062] The above describes the embodiments of the present invention in detail in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. For ordinary technicians in this field, several modifications and improvements can be made without departing from the present invention, and these should also be regarded as belonging to the protection scope of the present invention.

Claims

1. A method for manufacturing a stator core by winding with a yoke reinforcement, characterized in that: The invention comprises a stator core (2) formed by winding a steel strip (1) into a spiral stack, wherein the stator core comprises a yoke portion (3) and a tooth portion (4), wherein the tooth portion (4) is provided with tooth slots (10) arranged at equal intervals. The manufacturing method of the stator core comprises the following steps: Step 1, uncoiling and cutting: uncoiling the steel coil, cutting the raw material steel strip coil according to the set steel strip width requirement, and cutting the steel strip coil into a plurality of steel strips (1); Step 2: material sorting and leveling: the cut steel strip (1) is placed on a machine, and is trimmed into a flat and uniform long strip through a material unwinding machine, a leveling machine, and a material feeding machine; Step 3: punching, sending the leveled steel strip (1) to the feed inlet guide plate of the progressive die, so that the steel strip is gradually punched out with a center groove (20) and buckle points (5) according to a set step distance, and a continuous steel strip with a yoke (3), a tooth portion (4) and a connecting rib (6) is formed by punching, wherein the tooth root portion (41) of the tooth portion (4) is connected to the yoke portion (3), and the two ends of each connecting rib (6) are respectively connected to the tooth tip portions (42) of two adjacent tooth portions (4); Step 4: Steel strip winding: the stamped steel strip (1) is taken and fed into a winding mechanism, and is wound into a spiral loose semi-finished product with a predetermined number of turns, and each connecting rib (6) and yoke (3) is stretched or squeezed at the same time, and then separated into a single spiral monomer; Step 5: Connecting and fixing: placing the spiral monomer in the mold, aligning the buckle points (5) of the adjacent upper layer (11) and the buckle points (5) of the lower layer (12) and the center groove (20), pressing by a machine, and then connecting the adjacent upper layer (11) and the lower layer (12) to fix the spiral monomer into an integrated stator core preform; Step 6: Shaping: Shaping the stator core preform so that the dimensions of each phase of the product meet the standard; Step 7: Punching: Cut off the redundant connecting ribs, fix the stator core preform on the punching device, cut off the bent connecting ribs (6) in the stator core preform, and obtain the final stator core (2).

2. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 1, characterized in that: In step seven of the punching step, the punching device includes a support member arranged on the inner side of the tooth slot and a punch arranged on the outer side of the tooth slot. The punching device is used to punch from the outer side of the stator core to the inner side of the tooth slot to cut off the reserved connecting rib (6).

3. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 2, characterized in that: In the step five, the connection and fixing method also includes a welding or riveting process to fix the adjacent upper layer (11) and lower layer (12) steel strips (1).

4. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 3, characterized in that: The buckle points (5) are arranged in sequence at equal intervals along the length direction of the steel strip (1), and the buckle points (5) enable the upper layer (11) and the lower layer (12) of each steel strip (1) to be fixedly connected to each other after being wound and formed.

5. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 4, characterized in that: The buckle point (5) comprises a buckle point groove (50) and a buckle point protrusion (51). In step seven, the buckle point protrusion (51) of the upper layer (11) is snapped into the buckle point groove (50) of the lower layer (12), so that the upper layer (11) and the lower layer (12) are fixed.

6. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 5, characterized in that: Each of the buckling points (5) is arranged in the tooth portion (4) of the steel belt (1), and the buckling point (5) is rectangular or circular in shape.

7. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 6, characterized in that: The width of each yoke (3) is greater than the width of the connecting rib (6).

8. The method for manufacturing a stator core by winding with a yoke reinforcement according to claim 7, characterized in that: In the stator core (2), the tooth tip (42) of the tooth portion (4) faces the inside of the stator core (2), or the tooth tip (42) of the tooth portion (4) faces the outside of the stator core (2).

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