Insulator, motor, and blower

Abstract

An insulator (40) which insulates a coil and a core of a stator comprises: an annular part (41) that forms an annular shape along the outer periphery of the stator, and that is disposed at one end side of the core in the axial direction; a covering part (42) that protrudes radially inward from the annular part (41) and that covers a plurality of teeth formed in the core; and a protrusion (43) that protrudes from the annular part (41) toward the one end side of in the axial direction, and that guides a crossover wire which connect coils of the same phase from among coils wound on the teeth. The protrusion (43) has a column part (44) that protrudes toward the one end side in the axial direction from the annular part (41) and an inclined part (45) that extends toward the one end side in the axial direction from a tip end (44A) of the column part (44) and that has an inclined surface (45A) which is inclined so as to be further radially outward the further toward the one end side in the axial direction.

Description

Insulators, motors and blowers

[0001] The present invention relates to an insulator that insulates a stator core from a coil, a motor having the insulator, and a blower to which the motor is applied.

[0002] Generally, motor coils are constructed by winding wires around each of multiple teeth formed on a stator core, with insulators interposed between them. Coils wound around each tooth are connected by jumper wires, and a conventional guide structure has been proposed that routes the jumper wires radially outward relative to the coils.

[0003] For example, Patent Document 1 discloses an insulator structure having an outer wall portion erected along the axial direction of the coil on the radially outer side of the coil, and a protrusion portion protruding radially outward from the upper end side of the outer wall portion and approximately perpendicular to the axial direction. According to Patent Document 1, a crossover wire drawn from the coil is routed along the outer wall portion below the protrusion portion, and the protrusion portion arranged above the crossover wire restricts upward movement of the crossover wire, thereby preventing the crossover wire from riding up the outer wall portion.

[0004] International Publication No. 2019 / 004116

[0005] However, in the technology disclosed in Patent Document 1, which uses a protrusion protruding approximately perpendicular to the axial direction to restrict the upward movement of the crossover wire, if the crossover wire is positioned along the outer surface of the protrusion rather than below the protrusion during winding, it is difficult to guide the crossover wire to the appropriate position. In this case, the crossover wire may ride up the outer wall, potentially causing the winding to become unraveled. Therefore, there is room for improvement in the structure for guiding the crossover wire routed radially outward from the coil.

[0006] The insulator, motor, and blower of the present invention were devised in consideration of these problems, and one of their objectives is to properly maintain the function of guiding the jumper wire and prevent the coil winding from becoming unraveled. However, in addition to this objective, another objective of the present invention is to achieve effects that cannot be obtained by conventional techniques, which are derived from the configurations shown in the below-mentioned detailed description of the invention.

[0007] The disclosed insulator, motor, and blower can be realized as the following disclosed aspects (application examples) and solve at least part of the above-mentioned problems. Aspects 2 and 3 are both aspects that can be selected as appropriate and are both optional. Neither aspect 2 nor aspect 3 discloses an essential aspect or configuration for the present invention.

[0008] Aspect 1. The disclosed insulator is an insulator that insulates a core and a coil of a stator, and includes: an annular portion that is annular along the outer periphery of the stator and is arranged on one axial end side of the core; a covering portion that protrudes radially inward from the annular portion and covers a plurality of teeth formed on the core; and a protrusion that protrudes from the annular portion toward the one axial end side and guides a crossover wire that connects the coils of the same phase among the coils wound around each of the teeth, wherein the protrusion has a pillar portion that protrudes from the annular portion toward the one axial end side, and an inclined portion that extends from a tip of the pillar portion toward the one axial end side and has an inclined surface that inclines radially outward as it approaches the one axial end side.

[0009] Aspect 2. In the above-mentioned Aspect 1, it is preferable that the crossover wire is guided by the protrusion with a winding tension directed inward in the radial direction being applied. Aspect 3. In the above-mentioned Aspect 1 or 2, it is preferable that the axial dimension of the pillar portion is set to be smaller than a crossover wire height, which is the height dimension of a state in which multiple crossover wires are overlapped, and that the axial dimension of the protrusion is set to be larger than the crossover wire height.

[0010] Aspect 4. The disclosed motor includes the insulator according to any one of Aspects 1 to 3, a stator having a core around which a coil is wound via the insulator, and a rotor disposed radially opposite the stator. Aspect 5. The disclosed blower includes the motor according to Aspect 4, and an impeller fixed to a rotating shaft of the motor.

[0011] The disclosed insulator properly maintains the guide function of the protrusions and prevents the coil windings from becoming unraveled. Similar effects can also be achieved in a motor having the disclosed insulator and a blower using this motor.

[0012] Fig. 2 is a perspective view of an insulator according to an embodiment; Fig. 3 is an explanatory diagram of a blower to which a motor having the insulator of Fig. 1 is applied; Fig. 4 is a cross-sectional view of the blower of Fig. 2 taken along the line A-A; Fig. 5 is a cross-sectional view of the protrusion of the insulator of Fig. 1 taken along the line B-B; Figs. 1A and 1B are explanatory diagrams of the action and effect of the protrusion compared with the prior art; Figs. 1A and 1B are explanatory diagrams of the action and effect of the protrusion compared with the prior art; Figs. 2A and 2B are diagrams showing modified examples of the protrusion;

[0013] An insulator, a motor, and a blower will be described as embodiments with reference to the drawings. The embodiments described below are merely examples, and are not intended to exclude various modifications or applications of techniques not explicitly described in the following embodiments. The configurations of the present embodiments can be modified in various ways without departing from the spirit of the invention. Furthermore, they can be selected or combined as needed.

[0014] In the embodiment, an insulator for a motor used in a blower, i.e., an insulator for insulating a stator core and a coil, will be described as an example of an insulator. In the following description, the direction in which the motor's rotating shaft extends (rotational axis direction) is defined as the axial direction, and the direction perpendicular to the axial direction, away from the rotating shaft and toward the rotating shaft, is defined as the radial direction. Hereinafter, assuming that the axial direction is the up-down direction, one end side in the axial direction is referred to as the "upper" side (indicated by "U" in the figure), and the other end side opposite to this is referred to as the "lower" side (indicated by "L" in the figure). In addition, in the radial direction, the rotating shaft side is defined as the radially inner side, and the opposite side (the side away from the rotating shaft) is defined as the radially outer side. The direction perpendicular to the axial direction and going around the rotating shaft is defined as the circumferential direction.

[0015] [1. Configuration] Fig. 1 is a perspective view of an insulator 40 according to this embodiment. Fig. 2 is a plan view for explaining the configuration of a blower 1 to which a motor 10 having an insulator 40 according to this embodiment is applied, with the end bell 12 (see Fig. 3) omitted so that the internal structure can be seen. Fig. 3 is a cross-sectional view taken along the line A-A in Fig. 2. The blower 1 according to this embodiment is a fan that blows gas (e.g., air) by rotating an impeller 2 (see Fig. 3).

[0016] 2 and 3, the blower 1 includes an impeller 2, a motor 10 as a drive source for the impeller 2, and a blower housing 11 (hereinafter simply referred to as the "housing 11") that forms a case body that houses the impeller 2 and the motor 10. The motor 10 of this embodiment is an inner rotor type brushless motor, and includes a shaft 21 (rotational axis) having a rotation center X, a rotor 20 that rotates integrally with the shaft 21, and a stator 30 located radially outward of the rotor 20. The stator 30 is housed in the housing 11, and the rotor 20 is disposed radially opposite the stator 30 (inward in the radial direction in this embodiment).

[0017] The housing 11 has a cylindrical portion 11A with an internal arrangement space for accommodating the motor 10 (i.e., the rotor 20 and the stator 30), and an outer annular portion 11B outside the cylindrical portion 11A that forms an arrangement space for accommodating the impeller 2. One end of the shaft 21 protrudes from the underside of the housing 11, and the impeller 2 is fixed to this end. The impeller 2 is an impeller for blowing air, and is composed, for example, of a disk-shaped base fixed to the shaft 21 and a plurality of fins radially extending from the disk surface of the base. When the motor 10 operates and the shaft 21 rotates, the impeller 2 rotates integrally with the shaft 21.

[0018] A cover member (not shown) is attached to the underside of the housing 11. The housing 11 is combined with an end bell 12 (shown by a two-dot chain line in FIG. 3 ) and the cover member to form a case body of the blower 1. This case body has a substantially circular appearance when viewed from the axial direction, and the impeller 2 and motor 10 are disposed (accommodated) inside. The dimensions of the case body of the blower 1 are set so that at least the impeller 2 and motor 10 can be housed inside. In other words, making the motor 10 smaller and thinner contributes to making the case body of the blower 1 smaller and thinner.

[0019] 3, rotor 20 has a magnet 22 fixed to shaft 21 and two balancers 23 axially sandwiching magnet 22, and is rotatably fixed to housing 11 and end bell 12 by bearings 24. Stator 30 has a core (hereinafter referred to as "stator core") 31 fixed to the inner circumferential surface of housing 11, and a coil 35 wound around stator core 31 with insulator 40 interposed therebetween.

[0020] In this embodiment, as shown in Fig. 2, a stator 30 having six coils 35 arranged at equal intervals in the circumferential direction is taken as an example. That is, the stator core 31 has a generally annular shape centered on the rotation center X, and six teeth 31A are formed at equal intervals in the circumferential direction on the stator core 31. In the motor 10, a winding 35a is wound around each tooth 31A via an insulator 40, for example, in a Y-connection manner, to form the six coils 35.

[0021] The six coils 35 constitute one of the U, V, and W phases, and two coils 35 constituting the same phase are connected to each other by a jumper wire 36. Here, each coil 35 constituting the same phase is formed from a single (common) winding 35a wound around each tooth 31A, and the jumper wire 36 can be said to be a portion of the single winding 35a that is routed between the two coils 35 constituting the same phase. Specifically, of the six coils 35, two coils 35U constituting the U phase are connected to each other by a jumper wire 36U, two coils 35V constituting the V phase are connected to each other by a jumper wire 36V, and two coils 35W constituting the W phase are connected to each other by a jumper wire 36W.

[0022] Each jumper wire 36 is routed radially outward from the coil 35. The two coils 35U, 35V, and 35W constituting the same phase are arranged facing each other across the center of rotation X, as shown in Fig. 2, for example. In this structure, each jumper wire 36U, 36V, and 36W is routed radially outward from the coil 35 along the circumferential direction, making approximately half a turn.

[0023] The insulator 40 is a member that insulates the stator core 31 of the stator 30 from the coils 35, and is made of an insulating material (e.g., insulating resin). In addition to the basic function of insulating the stator core 31 from the coils 35 (insulating function), the insulator 40 of this embodiment also has a structure (guiding function) for appropriately guiding the jumper wires 36 routed radially outward from the coils 35.

[0024] 1, the insulator 40 includes an annular portion 41, a covering portion 42, and protrusions 43. The annular portion 41 is annular along the outer periphery of the stator 30, and is located on the upper side (one axial end side) of the stator core 31, forming a base where the covering portion 42 and the protrusions 43 are disposed. The annular portion 41 has an insulating function but does not have a direct guide function.

[0025] The covering portions 42 are portions that protrude radially inward from the annular portion 41 and cover the multiple teeth 31A (see FIGS. 2 and 3) formed on the stator core 31. In the insulator 40 of this embodiment, six covering portions 42 are formed at equal intervals in the circumferential direction, corresponding to the six teeth 31A that are formed at equal intervals in the circumferential direction. Each covering portion 42 covers a corresponding tooth 31A, and a winding 35a (see FIG. 2) is wound thereon. In other words, each covering portion 42 has an insulating function for insulating the corresponding tooth 31A from the coil 35 formed on that tooth 31A, but does not have a guiding function.

[0026] The protrusions 43 are portions that protrude upward (toward one axial end) from the annular portion 41 and guide the crossover wires 36 (see FIG. 2 ) that connect the coils 35 of the same phase among the coils 35 wound around each tooth 31A. That is, the protrusions 43 have a guide function in addition to an insulating function. In the insulator 40 of this embodiment, the same number of protrusions 43 as the number of coating portions 42 (i.e., six) are provided, and the circumferential positions of the coating portions 42 and the protrusions 43 are the same. That is, each protrusion 43 is located radially outward of each coating portion 42 (i.e., each coil 35), and the six protrusions 43 are provided at equal intervals in the circumferential direction.

[0027] Note that, when comparing the longest circumferential length of the covering portion 42 with the longest circumferential length of the protrusion 43, the former is longer, so to be precise, the protrusion 43 is provided within the range of the covering portion 42 in the circumferential direction. By arranging each protrusion 43 corresponding to each covering portion 42, the guide function is more appropriately exerted. Note that in Figure 2, only two of the six protrusions 43 are labeled with reference numerals, and the others are omitted.

[0028] 1 , the insulator 40 of this embodiment is provided with flange portions 46 that extend radially outward from the annular portion 41 in a flange-like shape. In this embodiment, the flange portions 46 are spaced apart from one another in the circumferential direction, and each flange portion 46 is located between circumferentially adjacent protrusions 43. The flange portions 46 have an insulating function for insulating the coil 35 from the jumper wire 36 routed above the flange portions 46. The flange portions 46 can also be said to have a guide function that allows the jumper wire 36 to be routed along the flange portions 46, and a partition function that restricts the routing position of the jumper wire 36 to within the space separated by the flange portions 46 so that the jumper wire 36 does not displace toward the coil 35.

[0029] The protrusion 43 guides the jumper wire 36 by positioning the jumper wire 36 connecting the coils 35 of the same phase radially outward from the protrusion 43 and bringing the jumper wire 36 into contact with the protrusion 43, thereby restricting the jumper wire 36 from being routed (placed) radially inward from the protrusion 43 and guiding (holding) it in the appropriate position.

[0030] In this embodiment, the crossover wire 36 is guided by the protrusion 43 with a winding tension applied radially inward. As described above, the crossover wire 36 is part of one winding wire 35a arranged between two coils 35 of the same phase. In order to properly form the coil 35, it is necessary to wind the winding wire 35a with an appropriate winding tension applied. Because the winding wire 35a of each coil 35 is wound with a winding tension applied, the crossover wire 36 between the coils 35 of the same phase is also similarly applied with a winding tension.

[0031] 2, the jumper wire 36 to which the winding tension is applied as described above is arranged radially outward of the coil 35 so as to make approximately half a turn along the circumferential direction, and is disposed radially outward of the protrusion 43. Therefore, the winding tension of the jumper wire 36 acts in a radially inward direction on the protrusion 43. Therefore, the jumper wire 36 is guided by the protrusion 43 with the winding tension applied to it in a radially inward direction, as described above.

[0032] Figure 4 is a cross-sectional view of one protrusion 43 taken in the axial direction along line B-B (a part of the radial line) shown in Figure 1. Since the multiple (six in this embodiment) protrusions 43 have the same configuration, the following description will be given using one protrusion 43 as an example to explain its configuration.

[0033] As shown in FIGS. 1 and 4 , the protrusion 43 includes a pillar portion 44 protruding from the annular portion 41 toward one axial end (here, the upper side) and an inclined portion 45 extending from a tip end 44A of the pillar portion 44 toward the one axial end. The pillar portion 44 is a portion of the protrusion 43 located toward the other axial end (here, the lower side) and has a generally rectangular parallelepiped shape. That is, the pillar portion 44 is located toward the base of the protrusion 43 and is a columnar portion with a uniform cross section in the axial direction. The crossover wire 36 is disposed along an outer surface 44B of the pillar portion 44 facing radially outward. The outer surface 44B is a curved surface that is slightly curved along the circumferential direction and extends along the axial direction. In this embodiment, the outer surface 44B extends in a direction perpendicular to the radial direction and is not inclined relative to the radial direction.

[0034] On the other hand, the inclined portion 45 is a portion of the protrusion 43 located toward one axial end (here, the upper side) and has an inclined surface 45A that slopes radially outward as it approaches the axial end. The inclined surface 45A is provided on the outer surface of the inclined portion 45 facing radially outward, and can be considered a surface that extends upward from the outer surface 44B of the base portion 44. The inclined portion 45 shown in FIG. 4 is formed on the outer surface facing radially outward, over the entire axial length from the tip end 44A of the base portion 44 to the tip end surface 45B of the inclined portion 45. In other words, in the cross-sectional shape shown in FIG. 4, the inclined surface 45A is inclined so as to linearly connect a radially outer position at the tip end 44A of the base portion 44 and a radially outer position (edge) at the tip end surface 45B of the inclined portion 45, and is actually a curved surface that is slightly curved along the circumferential direction.

[0035] Because the inclined surface 45A is inclined radially outward as it approaches the upper side, the crossover wire 36 arranged in contact with the pillar portion 44 is less likely to move upward from the pillar portion 44. Therefore, the inclined portion 45 has the function of preventing the crossover wire 36 arranged in contact with the pillar portion 44 from moving upward. The crossover wire 36 may also be arranged in contact with the inclined surface 45A. In this case, the crossover wire 36 arranged in contact with the inclined surface 45A is likely to be guided downward (to the other axial end, the appropriate position of the pillar portion 44) along the inclined surface 45A. Therefore, the inclined portion 45 also has the function of guiding the crossover wire 36 arranged in contact with the inclined surface 45A downward. The radially inner surface of the protrusion 43 is a uniform surface (a surface slightly curved in the circumferential direction) without any steps or inclinations at the pillar portion 44 and the inclined portion 45. This avoids unnecessary interference with the coil 35 located radially inside the protrusion 43.

[0036] The protrusions 43 are configured to guide one or more crossover wires 36. For example, as shown in FIG. 2 , in a motor 10 including three crossover wires 36U, 36V, and 36W, one protrusion 43 is configured to guide up to three crossover wires 36. In other words, the protrusions 43 are configured so that the above-described guide function of the protrusions 43 (particularly the inclined portions 45) can be properly performed even if three crossover wires 36 are arranged in contact with the protrusions 43. Specifically, as shown in FIG. 4 , the height H1, which is the axial dimension of the protrusions 43, is set to a height that can guide multiple crossover wires 36 (here, up to three). In the example shown in FIG. 4 , the height H1 of the protrusions 43 is the sum of the height H2 of the column portions 44 and the height H3 of the inclined portions 45.

[0037] More specifically, the height H1 of the protrusion 43 is set to be higher than the height dimension T of the multiple crossover wires 36 when they are overlapped (hereinafter referred to as the "crossover wire height T"). The height of the multiple crossover wires 36 when they are overlapped corresponds to a dimension that is equal to or slightly larger than the total dimension of the diameters R of the multiple crossover wires 36 that are overlapped (stacked) in the axial direction. If the height H1 of the protrusion 43 is set to be higher than the crossover wire height T, the multiple crossover wires 36 will not exceed the height H1 of the protrusion 43, and therefore the multiple crossover wires 36 arranged along the protrusion 43 can be properly guided.

[0038] The height H2 of the pillar portion 44 is set to an appropriate dimension that allows multiple (here, a maximum of three) crossover wires 36 to be arranged along the outer surface 44B of the pillar portion 44. As an example, from the viewpoint of satisfying both the objective of appropriately arranging the multiple crossover wires 36 on the protrusion portion 43 and the objective of suppressing the height H1 of the protrusion portion 43, the height H2 of the pillar portion 44 is set to be lower than the crossover wire height T, and the height H1 of the protrusion portion 43 is set to be higher than the crossover wire height T.

[0039] The height H3 of the inclined portion 45 is set to an appropriate height that can prevent the upward movement of the crossover wire 36 guided by the protrusion 43. The inclination of the inclined surface 45A (the angle of forward tilt toward the radially outward direction relative to the axial direction) is set to an appropriate angle that can prevent the upward movement of the crossover wire 36 guided by the protrusion 43.

[0040] As shown in FIG. 1 , the upper surface of each protrusion 43 is formed in a stepped shape with one circumferential end (here, the portion located clockwise when viewed from above) set lower than the other circumferential portions, and the inclined portion 45 is set shorter at the one circumferential end. When molding a resin molded product by injection molding, the gate position may be set at a position recessed from the end face to suppress interference between burrs generated at the gate position and other components. In each protrusion 43 of this embodiment, the insulator 40 can be molded by setting the gate position at the center of one circumferential end on the upper surface of each protrusion 43.

[0041] In this way, when the gate position is set at one circumferential end on the upper surface side of each protrusion 43, the circumferential width of the high-set portion (in this embodiment, the other circumferential portion of each protrusion 43) can be set longer while keeping the circumferential width of each protrusion 43 the same, compared to when the gate position is set at the circumferential center of each protrusion 43, that is, when the circumferential center of the upper surface side of each protrusion 43 is set low and both end portions are set high, creating a concave shape.

[0042] This can improve the strength of the other portions of the insulator 40 in the circumferential direction of each protrusion 43 after molding, which can ultimately contribute to improving the productivity of the motor 10. Furthermore, with this structure, when the crossover wire 36 is routed radially outward of the protrusion 43, the insulator 40 can be made lighter than a structure in which the height is increased overall in the circumferential direction while maintaining the contact area of ​​the crossover wire 36.

[0043] Finally, the structures of the motor 10 and the blower 1 will be described. The motor 10 includes the insulator 40 described above, a housing 11, a stator 30 housed in the housing 11, and a rotor 20 disposed radially opposite the stator 30. The blower 1 of this embodiment includes the motor 10 and an impeller 2 fixed to a shaft 21 (rotating shaft) of the motor 10.

[0044] [2. Effects] (1) In the insulator 40 described above, the protrusion 43 that guides the jumper wire 36 has an inclined portion 45 on one axial end side of the pillar portion 44 that protrudes from the annular portion 41, and this inclined portion 45 has an inclined surface 45A that inclines radially outward as it approaches the axial end. Therefore, when the jumper wire 36 is placed in contact with the pillar portion 44 during the winding operation of winding the winding wire 35a to form the coil 35, the inclined surface 45A of the inclined portion 45 makes it difficult for the jumper wire 36 to move toward the axial end. This makes it easier for the jumper wire 36 to remain in contact with the pillar portion 44.

[0045] Furthermore, when the crossover wire 36 is arranged in contact with the inclined surface 45A instead of the column portion 44, the crossover wire 36 is easily guided along the inclined surface 45A toward the other axial end. In other words, the crossover wire 36 arranged in contact with the inclined surface 45A is less likely to move toward the one axial end, and therefore the crossover wire 36 is less likely to come off the protrusion 43. Therefore, the guiding function of the protrusion 43 is properly maintained, and it is possible to prevent the winding 35a of the coil 35 from becoming unraveled.

[0046] (2) In the insulator 40 described above, the crossover wire 36 is guided by the protrusions 43 with a winding tension directed radially inward. Therefore, when the crossover wire 36 is placed in contact with the inclined surface 45A, a force directed toward the other axial end acts on the crossover wire 36, making it easier for the crossover wire 36 to move toward the other axial end along the inclined surface 45A. This more appropriately maintains the guiding function of the protrusions 43, and more effectively prevents the winding 35a of the coil 35 from becoming unraveled.

[0047] (3) In the insulator 40 described above, the axial dimension (height H2) of the pillar portion 44 is set lower than the crossover wire height T, which is the height dimension when multiple crossover wires 36 are stacked, and the axial dimension (height H1) of the protrusion 43 is set higher than the crossover wire height T. As described above, in this embodiment, the crossover wires 36 can also be arranged along the inclined portion 45 of the protrusion 43. Therefore, even if the height H2 of the pillar portion 44 is set lower than the crossover wire height T, multiple crossover wires 36 may be arranged up to above the height H2 of the pillar portion 44 (i.e., up to the position of the inclined portion 45). Furthermore, because the height H2 of the pillar portion 44 is set lower than the crossover wire height T, even if the inclined portion 45 is extended toward the tip of the pillar portion 44, the height H1 of the protrusion 43 can be reduced while ensuring a height at least higher than the crossover wire height T. Therefore, the height H1 of the protrusion 43 can be reduced without reducing the number of crossover wires 36 that can be guided by the protrusion 43.

[0048] 5 and 6 are explanatory diagrams relating to the effect described in (3) above. Figures 5(A) and 6(A) show the protrusion 43 of this embodiment, and Figures 5(B) and 6(B) show protrusions 143, 143' in which, instead of the inclined portion 45 as in the prior art, convex portions 145, 145' extending radially outward are provided. The convex portions 145, 145' of the protrusions 143, 143' shown in Figures 5(B) and 6(B) are both provided in a direction substantially perpendicular to the axial direction, and the crossover wire 36 cannot be placed along the convex portions 145, 145' (in contact with the radially outer surfaces).

[0049] 5A shows a protrusion 43 in which the height H2 of the pillar portion 44 is set lower than the crossover height T of the three crossover wires 36 when they are stacked together, and the height H1 of the protrusion 43 is set higher. With this protrusion 43, even if the height H2 of the pillar portion 44 is set lower than the crossover height T of the three crossover wires 36, parts of the three crossover wires 36 are arranged in contact with the inclined surface 45A of the inclined portion 45, so the three crossover wires 36 can be guided by the protrusion 43.

[0050] 5(B), in the case of a protrusion 143 in which the crossover wires 36 cannot be arranged along the convex portion 145, the height H12 of the column portion 144 must be set higher than the crossover wire height T in order to arrange three crossover wires 36. Therefore, when the height H13 of the protrusion 145 is set equal to the height H3 of the inclined portion 45, the height H11 of the protrusion 143 becomes larger than the height H1 of the protrusion 43. In other words, in the case of an insulator having this protrusion 143, the axial dimension becomes larger than that of the insulator 40 having the protrusion 43 of this embodiment.

[0051] 6(A) shows a protrusion 43 in which the height H2 of the pillar portion 44 is set lower than the crossover height T when three crossover wires 36 are overlapped, and the height H1 of the protrusion 43 is set higher, similar to FIG. 5(A). FIG. 6(B) shows a protrusion 143' in which the height H11' is set equal to the height H1 of the protrusion 43, and the height H12' of the pillar portion 144' is set lower than the crossover height T when three crossover wires 36 are overlapped. As shown in FIG. 6(B), in the protrusion 143', the height H12' of the pillar portion 144' is lower than the crossover height T of three crossover wires, so only a maximum of two crossover wires 36 can be placed.

[0052] 5 and 6, the protrusions 43 of this embodiment can be said to be able to reduce the height H1 of the protrusions 43 compared to the prior art without reducing the number of guideable crossover wires 36. Furthermore, because the height H1 of the protrusions 43 is reduced, the axial dimension (thickness) of the insulator 40 can be reduced. This contributes to a smaller and thinner motor 10, and ultimately to a smaller and thinner blower 1.

[0053] (4) The motor 10 having the insulator 40 described above can achieve at least the same effects as those described in (1) above for the insulator 40. Furthermore, the motor 10 including the insulator 40 having the configurations described in (2) and (3) above can also achieve the same effects as those described in (2) and (3) above.

[0054] (5) Furthermore, the blower 1 including the motor 10 and the impeller 2 fixed to the shaft 21 of the motor 10 can provide at least the same effects as those described in (4) above for the motor 10. Furthermore, by providing the blower 1 with the motor 10 including the insulator 40 having the configurations described in (2) and (3) above, the blower 1 can also provide the same effects as those described in (2) and (3) above.

[0055] [3. Other] The insulator 40, motor 10, and blower 1 described above are merely examples and are not limited to the above configurations. For example, the inclined portion 45 of the protrusion 43 is not limited to the above-described shape, i.e., a shape in which the inclined surface 45A is formed over the entire axial length from the tip 44A of the column portion 44 to the tip surface 45B of the inclined portion 45. As shown in the example of FIG. 7 , the inclined portion 45 may be a protrusion 43′ having an inclined surface 45A′ extending from the tip 44A of the column portion 44 to partway along one axial end (a portion of the axial range). In other words, the inclined surface 45A′ does not have to extend to the tip surface 45B′ of the inclined portion 45. In this case, a non-inclined surface 45C extending circumferentially and axially may be formed on the other axial portion of the inclined portion 45′ (toward the tip surface 45B′). In other words, in the cross-sectional shape shown in Figure 7, the inclined surface 45A' is inclined so as to linearly connect a radially outer position at the tip 44A of the column portion 44 and a position (lower edge of the non-inclined surface 45C) lower than the radially outer position (edge) at the tip surface 45B' of the inclined portion 45'.

[0056] The positions and number of the protrusions 43, 43' are not limited to the illustrated structure and may be changed as appropriate depending on the specifications of the coil 35. For example, the positions of the protrusions 43, 43' are not limited to the radially outer side of the covering portion 42, but may be circumferentially offset from the radially outer position of the covering portion 42. The number of covering portions 42 and the number of protrusions 43, 43' do not need to be the same. The number of covering portions 42 is required to be the same as the number of teeth 31A, but it is sufficient that the protrusions 43, 43' are provided at least at positions where the crossover wires 36 are routed. Furthermore, all of the protrusions 43, 43' do not necessarily have to have the same shape. For example, an insulator may be provided with the protrusion 43 shown in FIG. 4 and the protrusion 43' shown in FIG. 7, and the inclination of the inclined surface 45A may be changed (set) depending on the routing of the crossover wires 36.

[0057] Furthermore, the type of motor 10 is not limited to an inner rotor brushless motor, but may be an outer rotor motor or a brushed motor. The motor 10 having the insulator 40 described above is not limited to the blower 1, but may be applied to any equipment. An example of an object other than a blower to which the motor 10 can be applied is a plastic gearbox.

[0058] REFERENCE SIGNS LIST 1 Blower 2 Impeller 10 Motor 30 Stator 31 Stator core (core) 31A Teeth 35, 35U, 35V, 35W Coil 36, 36U, 36V, 36W Crossover wire 40 Insulator 41 Annular portion 42 Covering portion 43, 43' Projection portion 44 Pillar portion 44A Tip portion 45, 45' Inclined portion 45A, 45A' Inclined surface H1 Height (axial dimension of projection portion) H2 Height (axial dimension of pillar portion) T Crossover wire height

Claims

1. An insulator that insulates a stator core and coils, comprising: an annular portion that forms an annular shape along the outer periphery of the stator and is located on one axial end side of the core; a covering portion that protrudes radially inward from the annular portion and covers a plurality of teeth formed on the core; and a protrusion that protrudes from the annular portion toward the one axial end side and guides crossover wires that connect coils of the same phase among the coils wound around each of the teeth, wherein the protrusion has a pillar portion that protrudes from the annular portion toward the one axial end side, and an inclined portion that extends from the tip of the pillar portion toward the one axial end side and has an inclined surface that inclines radially outward as it approaches the one axial end side.

2. The insulator according to claim 1, wherein the crossover wire is guided by the protrusion while being subjected to winding tension directed inward in the radial direction.

3. An insulator as described in claim 1, characterized in that the axial dimension of the pillar portion is set to be smaller than the height of the crossover wires, which is the height dimension of the multiple crossover wires when they are stacked together, and the axial dimension of the protrusion portion is set to be larger than the height of the crossover wires.

4. A motor comprising: an insulator according to any one of claims 1 to 3; a stator having a core around which a coil is wound via said insulator; and a rotor disposed radially opposite said stator.

5. A blower comprising the motor according to claim 4 and an impeller fixed to the rotary shaft of the motor.