motor

Abstract

To improve productivity.SOLUTION: A stator provided in a motor, comprises: two connection parts, opposing to each other in a circumferential direction; an opening ring having multiple engaging parts; a fastening member to fasten the two connection parts; and multiple split cores. The multiple engaging parts of the opening ring engages with the multiple split cores.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to a motor.

Background Art

[0002] For example, motors mounted in vehicles are required to be miniaturized and have high output due to the increasing number and large capacity of the mounted devices. In order to realize a miniaturized and high-output motor, it is necessary to increase the occupation ratio of the winding. In order to realize an increase in the occupation ratio of the winding, a motor employs a split core structure in which a plurality of cores are divided in the circumferential direction.

[0003] For example, Patent Document 1 describes a motor that employs a structure in which a plurality of cores are divided in the circumferential direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the technology described in Patent Document 1 has room for further improvement from the viewpoint of improving productivity.

[0006] The present invention has been made in view of the above, and an object thereof is to provide a motor capable of improving productivity.

Means for Solving the Problems

[0007] In order to solve the above-described problems and achieve the object, a stator included in a motor according to the present invention includes an open ring having two connecting portions facing each other in the circumferential direction and a plurality of engaging portions, a fastening member that fastens the two connecting portions, and a plurality of split cores. The fastening member is fastened to the two connecting portions in the axial direction.The multiple engagement portions of the open ring engage with the multiple segmented cores.

[0008] According to one embodiment of the motor of the present invention, productivity can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a plan view of the motor according to the embodiment. [Figure 2] Figure 2 is a perspective view of the stator of the motor shown in Figure 1. [Figure 3] Figure 3 is a perspective view of the annular member and segmented core of the stator shown in Figure 2. [Figure 4] Figure 4 is a plan view showing a portion of the annular member and segmented core shown in Figure 3. [Figure 5] Figure 5 is a plan view showing the annular member shown in Figure 4 with the segmented core connected to it. [Figure 6] Figure 6 is a plan view of the rings included in the stator shown in Figure 2. [Figure 7] Figure 7 is a perspective view of a portion of the ring shown in Figure 6 and the fastening members of the stator shown in Figure 2. [Figure 8] Figure 8 is a rear view of a portion of the ring and fastening member shown in Figure 7. [Figure 9] Figure 9 is a perspective view showing the attachment of rings and fastening members to the annular member and segmented core of the stator shown in Figure 2. [Figure 10] Figure 10 is a cross-sectional view of a portion of the stator shown in Figure 2. [Modes for carrying out the invention]

[0010] The motor according to the embodiment will be described in detail below based on the drawings. Note that the dimensional relationships and ratios of the elements in the drawings may differ from reality. There may also be differences in dimensional relationships and ratios between elements within the drawings themselves.

[0011] [Embodiment] Figure 1 is a plan view of a motor 1 according to an embodiment. Figure 2 is a perspective view of the stator 4 included in the motor 1 shown in Figure 1. Figure 3 is a perspective view of the annular member 41 and the divided core 42 included in the stator 4 shown in Figure 2. Figure 4 is a plan view showing a part of the annular member 41 and the divided core 42 shown in Figure 3. Figure 5 is a plan view of the state in which the divided core 42 is connected to the annular member 41 shown in Figure 4. Figure 6 is a plan view of the ring 45 included in the stator 4 shown in Figure 2. Figure 7 is a perspective view of a part of the ring 45 shown in Figure 6 and the fastening member 46 included in the stator 4 shown in Figure 2. Figure 8 is a rear view of a part of the ring 45 and the fastening member 46 shown in Figure 7. Figure 9 is a perspective view of the ring 45 and fastening member 46 being attached to the annular member 41 and the divided core 42 of the stator 4 shown in Figure 2. Figure 10 is a cross-sectional view of a part of the stator 4 shown in Figure 2. Note that in Figures 2, 3, 4, 5, and 10, the coil 44 of the stator 4 has been omitted for the sake of clarity.

[0012] In the description of the motor 1 shown in Figures 1 to 10 according to the following embodiment, in order to facilitate understanding of direction, the direction in which the shaft 2 (described later) extends will be referred to as the axial direction A, and the direction in which the rotor 3 (described later) rotates will be referred to as the circumferential direction C. Furthermore, the direction that is included in the plane perpendicular to the axial direction A, passes through the axis 2o of the shaft 2, and is perpendicular to the circumferential direction C will be referred to as the radial direction R.

[0013] The motor 1 shown in Figure 1 according to this embodiment is an inner rotor type in which, when viewed from the axial direction A, the stator 4 is located outside the rotor 3 in the radial direction R, while the shaft 2 is located inside the rotor 3 in the radial direction R. The motor 1 according to this embodiment is, for example, a three-phase motor (DC motor) that is electrically connected to a three-phase AC power supply.

[0014] The motor 1 according to this embodiment is an electric motor that converts electrical energy from a power source, for example, into a driving force that rotates the shaft 2 in the circumferential direction C. The motor 1 is housed in a frame, for example, not shown.

[0015] The motor 1 includes, for example, a shaft 2, a rotor 3, and a stator 4. The shaft 2 is a so-called rotating shaft, and is formed, for example, in a columnar shape extending along the axial direction A from a metal member. The shaft 2 has an axis 2o and is provided so as to be rotatable about the axis 2o. Then, the shaft 2 transmits power to the outside by rotating in the circumferential direction C.

[0016] The rotor 3 is provided so as to be rotatable about the axis 2o of the shaft 2. The rotor 3 according to the present embodiment is arranged to face the stator 4 in the radial direction R and is fixed to the shaft 2, for example. Further, the motor 1 according to the present embodiment integrally forms the shaft 2 and the rotor 3.

[0017] The rotor 3 is arranged inside the stator 4 in the radial direction R, for example. That is, the motor 1 is an inner rotor type brushless motor in which the rotor 3 is located inside the stator 4 in the radial direction R.

[0018] The rotor 3 has a yoke 31 and magnets 32. The yoke 31 is formed of a magnetic material such as iron, for example.

[0019] The magnet 32 is constituted by a permanent magnet, for example. The rotor 3 according to the present embodiment has, for example, eight magnets 32.

[0020] The stator 4 is a part that generates a force for rotating the rotor 3 in the circumferential direction C. As shown in FIG. 2, the stator 4 includes, for example, one annular member 41, a plurality of divided cores 42, a plurality of insulators 43, a plurality of coils 44 (see FIG. 1), one ring 45, and one fastening member 46.

[0021] The annular member 41 is formed by laminating plate-shaped metal members such as silicon steel sheets, electrical steel sheets, or soft magnetic steel sheets in the axial direction A, and is magnetic and annular when viewed from the axial direction A. Furthermore, as shown in Figure 3, the stator 4 according to this embodiment employs a so-called I-type split core structure in which the annular member 41 and the split core 42 are formed separately.

[0022] The annular member 41 has a main body 411 and a plurality of first grooves 412 formed in the main body 411. The first grooves 412 extend in the axial direction A and are formed on the inner circumferential surface of the main body 411. The number of first grooves 412 corresponds to the number of segmented cores 42, and the plurality of first grooves 412 are arranged at equal intervals with respect to the circumferential direction C.

[0023] As shown in Figure 4, the first groove 412 comprises a first side wall 4121 extending in the circumferential direction C, a pair of second side walls 4122 extending in the radial direction R, a pair of third side walls 4123 extending in the radial direction R, and a pair of stepped portions 4124. The first side wall 4121 is along the outer circumferential surface of the annular member 41.

[0024] The pair of second side walls 4122 face each other in the circumferential direction C. The pair of second side walls 4122 are connected to both ends of the first side wall 4121, respectively. Furthermore, the pair of second side walls 4122 are inclined such that their distance from each other gradually increases in the radial direction R from the inside to the outside.

[0025] The pair of third side walls 4123 face each other in the circumferential direction C. Each of the third side walls 4123 is located radially inward R relative to the second side wall 4122. The pair of third side walls 4123 extend radially R such that they are at a constant distance from each other in that direction. The pair of stepped portions 4124 connect to the ends of the second side wall 4122 that are located radially inward R, and to the ends of the third side wall 4123 that are located radially outward R. Each of the pair of stepped portions 4124 has a step in the radial direction R.

[0026] Each of the segmented cores 42 shown in Figure 3 is a so-called tooth. In this embodiment, the segmented cores 42 can be connected to the inner circumferential surface of the annular member 41. In other words, the stator 4 includes an annular member 41 to which multiple segmented cores 42 are connected. The number of segmented cores 42 corresponds to the number of coils 44, and the multiple segmented cores 42 are arranged at equal intervals with respect to the circumferential direction C. Each segmented core 42 has a first portion 421 extending along the circumferential direction C and a second portion 422 extending along the radial direction R, and when viewed from the axial direction A, each segmented core 42 is formed in a T-shape. The first portion 421 of the segmented core 42 faces the rotor 3 and becomes the magnetic pole portion. The second portion 422 of the segmented core 42 is a spoke connecting the first portion 421 and the annular member 41.

[0027] At the end of the second portion 422 located on the radial side R, a portion 4220 (hereinafter referred to as the insertion portion) is formed which is inserted into the first groove 412. As shown in Figure 4, the insertion portion 4220 is composed of a first side surface 4221, a pair of second side surfaces 4222, a pair of third side surfaces 4223, and a pair of fourth side surfaces 4224. The pair of fourth side surfaces 4224 are surfaces that face and connect to the annular member 41.

[0028] The first side surface 4221 connects to the inner end of one of the pair of second side surfaces 4222 located in the radial direction R, and also connects to the inner end of the other second side surface 4222 located in the radial direction R. The pair of second side surfaces 4222 face each other in the circumferential direction C. Each of the pair of second side surfaces 4222 extends radially R such that the distance between them is constant in the radial direction R.

[0029] The pair of third sides 4223 face each other in the circumferential direction C. Furthermore, the pair of third sides 4223 are positioned outside the pair of second sides 4222 in the circumferential direction C. The pair of third sides 4223 are inclined such that their distance from each other gradually increases in the radial direction R from the inside to the outside.

[0030] A pair of fourth sides 4224 are positioned at the outermost radial R of the second portion 422. Each of the fourth sides 4224 connects to the outer end of the second side 4222 located radially R, and also connects to the outer end of the third side 4223 located radially R. In other words, each of the fourth sides 4224 connects the second side 4222 and the third side 4223.

[0031] Next, the connection of the divided core 42 to the annular member 41 will be explained using Figures 3 and 5. First, as shown in Figure 3, the worker places the divided core 42 on one side in the axial direction A relative to the annular member 41.

[0032] The worker then moves the divided core 42 to the other side in the axial direction A relative to the annular member 41, thereby connecting the divided core 42 to the annular member 41. During this movement, the divided core 42 is connected to the annular member 41 by inserting the insertion part 4220 into the first groove 412. In this state, with the divided core 42 connected to the annular member 41, the divided core 42 is temporarily fixed to the annular member 41.

[0033] Furthermore, as shown in Figure 5, when the divided core 42 is connected to the annular member 41, in the circumferential direction C, the second side wall 4122 of the annular member 41 and the third side surface 4223 of the divided core 42 face each other, and the third side wall 4123 of the annular member 41 and the side surface of the tip of the second portion 422 of the divided core 42 face each other. Moreover, in this state, the first side wall 4121 of the annular member 41 and the first side surface 4221 of the divided core 42 face each other in the radial direction R.

[0034] In addition, in this state, a hole 47 is formed by the first side wall 4121 of the annular member 41 and the pair of second side surfaces 4222 and first side surfaces 4221 of the divided core 42. The hole 47 extends in the axial direction A and has an engaged portion 471 (see Figure 10) that engages with an engaging portion 454, which will be described later. Both ends of the hole 47 in the axial direction A are open. The engaged portion 471 extends in the axial direction A from an opening located on one side of the hole 47 in the axial direction A. In other words, the engaged portion 471 is located on one side of the hole 47 in the axial direction A. Furthermore, if the directions perpendicular to the radial direction R and the axial direction A are referred to as the width direction, the length of the hole 47 in the width direction is W2, and the length of the hole 47 in the radial direction R is L2.

[0035] Furthermore, in this state, each of the multiple segmented cores 42 protrudes inward in the radial direction R (i.e., toward the rotor 3) from the inner circumferential surface of the annular member 41, as shown in Figure 1.

[0036] The segmented core 42 passes inside the coil 44 in the radial direction R. The stator 4 according to this embodiment comprises, for example, 12 segmented cores 42.

[0037] The insulator 43 is formed of, for example, an insulating resin. The insulator 43 is provided on each of the segmented cores 42. Furthermore, each of the insulators 43 is mounted on the surface of the segmented core 42, ensuring insulation between the segmented core 42 and the coil 44 (see Figures 9 and 10). The stator 4 according to this embodiment comprises, for example, 12 insulators 43.

[0038] The multiple coils 44 shown in Figure 1 are arranged, for example, at equal intervals along the circumferential direction C. Although not shown in the illustration, the coils 44 in this embodiment have a high-space-occupancy winding, which allows the motor 1 to be miniaturized and to have high output. Furthermore, the motor 1 in this embodiment includes, for example, 12 coils 44.

[0039] The ring 45 is formed, for example, by punching out a sheet of metal. As shown in Figure 6, for example, the ring 45 has one body 451 extending in the circumferential direction C, one notch 452 formed in the body 451, two connecting portions 453a, 453b facing each other in the circumferential direction C, and a plurality of engaging portions 454.

[0040] The main body 451 is annular when viewed from the axial direction A, and as shown in Figure 7, it has a surface 451f perpendicular to the axial direction A. A recess 451a is also formed in the main body 451. In the circumferential direction C, the position where the recess 451a is formed coincides with the position where the engaging portion 454 is formed. The recess 451a is formed on the outer edge of the main body 451 and is formed to be recessed from the outside to the inside in the radial direction R.

[0041] Furthermore, the main body 451 has a first end 451b and a second end 451c that face each other across a notch 452. When no external force is applied to the ring 45, the first end 451b and the second end 451c are separated by a predetermined width in the circumferential direction C. However, when an external force is applied, the ring 45 is elastically deformable so that the first end 451b and the second end 451c are separated by a width greater than the predetermined width in the circumferential direction C. In other words, when the ring 45 is elastically deformed in the directions of arrows F1 and F2 shown in Figure 1, the outer shape (diameter) of the ring 45 increases as the first end 451b and the second end 451c separate from each other.

[0042] The notch 452 is formed in the main body 451 so as to extend radially R midway along the circumferential direction C, and divides the main body 451 midway along the circumferential direction C.

[0043] The two connecting portions 453a and 453b face each other in the circumferential direction C, with the notch 452 in between. In other words, of the two connecting portions 453a and 453b, one connecting portion 453a is located at the first end portion 451b on one side of the circumferential direction C of the main body 451, and the other connecting portion 453b is located at the second end portion 451c on the other side of the circumferential direction C of the main body 451. Furthermore, the two connecting portions 453a and 453b in this embodiment are formed to protrude inward in the radial direction R from the inner circumferential edge of the main body 451.

[0044] Each of the connecting portions 453a and 453b has a curved shape (arc-shaped) when viewed from the axial direction A, and in the circumferential direction C, a space 453s into which the fastening member 46 is inserted is located between the two connecting portions 453a and 453b. A thread is formed on the inner periphery of the space 453s in this embodiment. Furthermore, the space 453s is circular when viewed from the axial direction A, and the diameter of the space 453s is 453r (see Figure 8).

[0045] Each of the engaging portions 454 has a bent portion 454a that bends from the surface 451f of the main body 451 and a protruding portion 454b that extends in the axial direction A. In other words, the engaging portion 454 includes a protruding portion 454b that extends in the axial direction A. Each of the protruding portions 454b shown in Figure 8 has a rectangular cross-section perpendicular to the axial direction A and has a pair of first side surfaces 4541 that face each other in the circumferential direction C and a pair of second side surfaces 4542 that face each other in the radial direction R. The number of engaging portions 454 corresponds to the number of segmented cores 42, and the multiple engaging portions 454 are arranged at equal intervals with respect to the circumferential direction C.

[0046] Furthermore, if we refer to the directions perpendicular to the radial direction R and the axial direction A as the width direction, the length W1 of the protruding portion 454b in the width direction is shorter than the length W2 of the hole portion 47 in the width direction (see Figure 5), and the length L1 of the engaging portion 454 in the radial direction R is shorter than the length L2 of the hole portion 47 in the radial direction R (see Figure 5). For these reasons, by inserting the protruding portion 454b into the hole portion 47, it is possible to engage the engaging portion 454 of the ring 45 with the split core 42. When the engaging portion 454 is inserted into the hole portion 47, the protruding portion 454b is positioned inside the hole portion 47 (see Figure 10).

[0047] As shown in Figure 7, the fastening member 46 has a first end portion 46a on one side in the axial direction A into which the tip of a tool fits, and a second end portion 46b on the other side in the axial direction A, which has a spiral recess or protrusion formed on its outer circumferential surface. The spiral recess or protrusion formed on the outer circumferential surface of the second end portion 46b of the fastening member 46 can be screwed into the spiral recess or protrusion formed on the inner circumferential surfaces of the connecting portions 453a and 453b. The diameter 46r of the second end portion 46b is larger than the diameter 453r of the space portion 453s.

[0048] Next, the process of assembling the ring 45 and fastening member 46 to the annular member 41 and the divided core 42 in the stator 4 according to this embodiment will be explained with reference to Figures 9 and 10.

[0049] First, the worker places the ring 45 on one side of the segmented core 42 in the axial direction A, as shown in Figure 9. Next, the worker applies adhesive to the other side of the ring 45 in the axial direction A (the back surface located opposite the surface 454f in the axial direction A). Then, as the worker moves the ring 45 to the other side in the axial direction A relative to the annular member 41, the worker inserts the multiple engaging parts 454 into the multiple holes 47, and the worker stacks the ring 45 on the multiple segmented cores 42 in the axial direction A.

[0050] Next, the worker positions the fastening member 46 on one side of the ring 45 in the axial direction A. Then, the worker fits a tool onto the tip of the first end 46a located on one side of the fastening member 46 in the axial direction A, and then moves the fastening member 46 to the other side in the axial direction A, bringing the fastening member 46 into contact with the connecting portions 453a and 453b.

[0051] Next, the worker rotates the tool. As a result, the spiral concave or convex shape on the outer surface of the second end 46b of the fastening member 46 engages with the spiral concave or convex shape on the inner surface of the connecting portion 453a, 453b. This causes the fastening member 46 to move to the other side in the axial direction A of the ring 45, and simultaneously, in the circumferential direction C, the first end 451b on one side and the second end 451c on the other side separate, causing the ring 45 to elastically deform. In other words, the ring 45 opens up, and the outer diameter of the ring 45 increases.

[0052] As a result, in the circumferential direction C, the first side surface 4541 (see Figure 8) of the engaging portion 454, which is away from the notch 452 of the ring 45, contacts and then presses against the second side surface 4222 (see Figure 5) of the hole 47. Therefore, when the fastening member 46 is fastened to the two connecting portions 453a and 453b, the first end 451b on one side of the ring 45 and the second end 451c on the other side open up, and the opened ring 45 applies stress to the annular member 41 in the circumferential direction C. Then, the protruding portion 454b of the ring 45 applies stress to the annular member 41, causing the multiple segmented cores 42 to be fixed to the annular member 41 from a temporarily fixed state.

[0053] As described above, in this embodiment, the motor 1 has multiple engaging portions 454 of the ring 45 that opens in the circumferential direction C that engage with multiple divided cores 42.

[0054] In this embodiment, the engaging portion 454 of the motor 1 includes a protruding portion 454b extending in the axial direction A, and the engaged portion 471 that engages with the engaging portion 454 includes a hole 47 extending in the axial direction A. When the engaging portion 454 and the engaged portion 471 are engaged, the protruding portion 454b is positioned inside the hole 47.

[0055] In this embodiment, the length W1 in the width direction of the protrusion 454b is shorter than the length W2 in the width direction of the hole 47, and the length L1 in the radial direction R of the protrusion 454b is shorter than the length L2 in the radial direction R of the hole 47. Therefore, compared to a motor in which the tooth body is attached to an annular member, the process of pressing in pins corresponding to the number of split cores 42 is eliminated by press-fitting pins into the pin holes of each tooth body corresponding to the split core 42, thus improving the productivity of the motor 1 according to this embodiment. Furthermore, in the motor 1 according to this embodiment, by connecting one fastening member 46 to the connecting portions 453a and 453b of one ring 45, the first side surface 4541 of the engaging portion 454 can be pressed against the second side surfaces 4222 of multiple holes 47, thus further improving productivity.

[0056] In this embodiment, the multiple stators 4 include an annular member 41 connected to the multiple segmented cores 42, and the ring 45 applies stress to the segmented cores 42 against the annular member 41 in the circumferential direction C.

[0057] In this embodiment, the ring 45 is stacked on a plurality of segmented cores 42 in the axial direction A.

[0058] In this embodiment, the stator 4 has a ring 45 attached to an annular member 41 via adhesive in the axial direction A. Therefore, the stator 4 in this embodiment can firmly fix the ring 45 to the annular member 41.

[0059] In the circumferential direction C, the position where the recess 451a is formed coincides with the position where the engaging portion 454 is formed. The recess 451a is formed on the outer peripheral edge of the main body 451 and is formed to be recessed from the outside to the inside in the radial direction R. Therefore, when viewed from the axial direction A, the worker can see the recess 451a and the hole 47 at the same time, making it easy to insert the engaging portion 454 into the hole 47.

[0060] In the motor 1 according to the above embodiment, threads are formed on the inner circumferential surfaces of the connecting portions 453a and 453b, and a spiral concave or convex shape is formed on the outer circumferential surface of the second end portion 46b in the axial direction A of the fastening member 46. However, the coil 44 according to this embodiment is not limited to this. For example, in the motor 1 according to this embodiment, it is not necessary to necessarily form a spiral concave or convex shape on the inner circumferential surfaces of the connecting portions 453a and 453b, nor is it necessary to necessarily form a spiral concave or convex shape on the outer circumferential surface of the second end portion 46b in the axial direction A of the fastening member 46.

[0061] Furthermore, in the motor 1 according to the above embodiment, a case was described in which the ring 45 is attached to the annular member 41 via adhesive in the axial direction A. However, the motor 1 according to this embodiment is not limited to this. For example, in the motor 1 according to this embodiment, it is not always necessary to provide adhesive between the annular member 41 and the ring 45 in the axial direction A.

[0062] Furthermore, the stator 4 according to the above embodiment was described as comprising one annular member 41, twelve segmented cores 42, and one ring 45. However, the stator 4 according to this embodiment is not limited to this. For example, the number of segmented cores 42 in the stator 4 can be set to any number of three or more.

[0063] Furthermore, the motor 1 described in the above-described embodiment is of the inner rotor type. However, the motor 1 according to this embodiment is not limited to that. For example, the motor 1 according to this embodiment can be applied to an outer rotor type in which the stator 4 is located inside the rotor 3 in the radial direction R when viewed from the axial direction A.

[0064] The above description is based on embodiments of the motor 1 according to the present invention, but it goes without saying that the present invention is not limited to these embodiments, and various modifications are possible without departing from the spirit of the invention. Combinations of the components of each of the embodiments described above are also included in the present invention. Various modifications that do not depart from the spirit of the invention are also included in the technical scope of the present invention, and this will be clear to those skilled in the art from the description of the claims. [Explanation of symbols]

[0065] 1 Motor, 4 Stator, 41 Annular member, 42 Split core, 45 Ring, 453a Connecting part, 453b Connecting part, 454 Engaging part, 454b Protruding part, 46 Fastening member, 47 Hole, 471 Engaged part, C Circumferential direction

Claims

1. An open ring having two connecting parts facing each other in the circumferential direction, and a plurality of engaging parts, A fastening member for fastening the two connecting parts, Multiple partitioned cores, Equipped with a stator having, The fastening member is fastened to the two connecting portions in the axial direction. The multiple engaging portions of the open ring engage with the multiple segmented cores. Motor.

2. The engaging portion includes a projection that extends in the axial direction, The engaged portion that engages with the engaging portion has a hole that extends in the axial direction, The aforementioned protrusion is located inside the hole. The motor according to claim 1.

3. The stator comprises an annular member connected to the plurality of segmented cores, The ring is such that the fastening member opens the ring, thereby applying circumferential stress to the segmented core relative to the annular member. The motor according to claim 1 or 2.

4. In the axial direction, the ring is stacked on the plurality of segmented cores. The motor according to claim 1 or 2.

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