Motor stator

An insulator includes an extended portion extended along the axial direction of a motor stator from an annular member. The extended portion includes at least one protruding portion protruding in the outer-diameter direction from a guide surface that guides a winding in the circumferential direction of a motor stator. This protruding portion includes an abutting surface capable of abutting the winding guided by the guide surface. The abutting surface includes a slant portion that comes close to the annular member toward the outer-diameter direction. The slant portion is capable of abutting a semicircular portion of the winding with the circular cross-sectional shape at the outer-diameter side.

FIELD OF THE INVENTION

The present disclosure relates to a motor stator that causes a winding to be wound therearound along an outer-circumference surface of an insulator.

BACKGROUND

A motor stator includes a core that is formed by laminating magnetic steel sheets, etc., and an insulator that is attached to this core. Japan Patent No. 5532274 B discloses a conventional technology relating to an insulator.

Japan Patent No. 5532274 B discloses a three-phase and 12-slot motor stator. An insulator of this stator includes an annular member at an outer-diameter side, 12 extended portions extended from this annular member in the axial direction of the motor stator, and 12 wind portions which is extended from the annular member in the inner-diameter direction, and around which a winding is respectively wound.

For the purpose of description, one wind portion among the 12 wind portions will be defined as a first wind portion, and the other wind portions will be defined as, with reference to the center line of the motor stator, second to 12th wind portions in the clockwise direction. Similarly, the extended portion located at the outer-diameter side of the first wind portion will be defined as a first extended portions, and the other extended portions will be defined as second to 12th extended portions in the clockwise direction.

An example wire connection scheme for a winding will be described. First, the winding is wound around the first wind portion. Next, the winding is drawn out to the outer-circumference side of the first extended portion, and the winding is caused to be drawn along the outer-circumference surface (a guide surface) of the second extended portion, and the outer-circumference surface (a guide surface) of the third extended portion. Subsequently, the winding is wound around the fourth wind portion located at the internal-diameter side of the fourth extended portion. Similarly, the winding is wound around the seventh wind portion and the 10th wind portion. Accordingly, formation of the winding in a phase among the three-phases is completed. The winding to the wind portion and drawing along the outer-circumference surface of the extended portion are repeated, and thus formation of the windings in the remaining two phases is completed.

A protruding portion that protrudes in the outer-diameter direction is provided in the outer-circumference surface of each extended portion. When the winding along the guide surface of the extended portion is displaced in the axial direction of the motor stator, the protruding portion restricts the winding so as not to be detached from the extended portion of the insulator.

In order to surely cause the winding to be wound around each wind portion, it is desirable to further enhance a preventing function for the winding from being detached from the extended portion of the insulator.

SUMMARY OF THE INVENTION

An objective of the present disclosure is to provide a technology capable of causing a winding guided in a circumferential direction of an insulator to be retained on a guide surface of the insulator.

A motor stator according to a first embodiment of the present disclosure includes:

a core;

an insulator covering the core; and

a coil formed by a winding wound around the insulator.

The core includes: an annular yoke; and a tooth extended from the yoke in an inner-diameter direction of the motor stator.

The insulator includes: an annular member covering the yoke; a wind portion which covers the tooth and around which the winding is wound; and an extended portion extended from the annular member along an axial direction of the motor stator.

The extended portion includes at least one protruding portion that protrudes in an outer-diameter direction from a guide surface which guides the winding in a circumferential direction of the motor stator.

The protruding portion includes an abutting surface capable of abutting the winding guided by the guide surface.

The abutting surface includes a slant portion that becomes close to the annular member toward the outer-diameter direction.

The slant portion is capable of abutting any portion of a half of the winding at an outer-diameter side.

According to a second embodiment of the present disclosure, preferably, a terminal is attached to a tip surface of the extended portion, the terminal includes a connection portion capable of being electrically connected to the winding guided by the guide surface, the two protruding portions adjacent to each other in the circumferential direction are provided on the guide surface of the extended portion, and as viewed from the axial direction of the motor stator, the connection portion is located between the two protruding portions in the circumferential direction.

According to the above first embodiment, the insulator for the motor stator includes the annular member covering the yoke, and the extended portion extended from the annular member along the axial direction of the motor stator. The extended portion includes at least one protruding portion that protrudes in the outer-diameter direction from the guide surface which guides the winding in the circumferential direction of the motor stator. The protruding portion includes the abutting surface capable of abutting the winding guided by the guide surface. Accordingly, if the winding guided in the circumferential direction is moved in the axial direction, the winding abuts the abutting surface of the protruding portion.

Moreover, the abutting surface includes the slant portion that becomes close to the annular member toward the outer-diameter direction. The slant portion is capable of abutting any portion of the half of the winding at the outer-diameter side. Accordingly, even if the winding is moved in the outer-diameter direction, the winding abuts the abutting surface. In view of the foregoing, even if the winding is moved not only in the axial direction of the motor stator but also in the outer-diameter direction, the winding abuts the abutting surface. This enables the winding to be retained at the predetermined position.

According to the above second embodiment, the terminal which is electrically connectable to the exterior is attached to the tip surface of the extended portion extended from the annular member of the core in the axial direction. The terminal includes the connection portion capable of being electrically connected to the winding. The two protruding portions adjacent to each other in the circumferential direction are provided on the guide surface of the extended portion. As viewed from the axial direction of the motor stator, the connection portion is located between the two protruding portions, and the winding abuts the abutting surface of the one protruding portion, the connection portion, and the other protruding portion.

Accordingly, when the winding guided along the guide surface is connected to the connection portion, by causing the winding to abut the abutting surface of the one protruding portion, the winding can be bent with the one protruding portion being as an origin. Since the bent portion of the winding is held by the one protruding portion, it becomes easy to put the winding across the connection portion. Moreover, the winding extended from the connection portion to the other protruding portion is caught by the other protruding portion. This facilitates subsequent works of guiding the winding in the circumferential direction and of drawing the winding in the inner-diameter direction.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments will be described with reference to the accompanying drawings. Note that, in the following description, an inner-diameter direction, an outer-diameter direction, a circumferential direction, and an axial direction (a vertical direction) will be defined with reference to a center line C of a motor stator. The portion with the same shape will be denoted by the same reference numeral, and the description thereof will be omitted as appropriate.

With reference toFIG. 1andFIG. 2, a motor stator10according to an embodiment includes a core11formed of a large number of laminated magnetic steel sheets, a first insulator20that covers the upper portion of this core11, a second insulator30that covers the lower portion of the core11, first coils U1, V1, and W1, second coils U2, V2, and W2, and third coils U3, V3, and W3which are provided on the first insulator20and on the second insulator30, and a first terminal15to a third terminal17that are attached to the first insulator20.

With reference toFIG. 2, the core11includes an annular yoke12, and nine teeth13extended the inner-diameter direction from the yoke12. A tip13aof each tooth13has a width that increases in the circumferential direction along the inner-diameter direction.

The first insulator20includes a first annular member21capable of covering the upper portion of the yoke12, nine first wind portions22each capable of covering the upper half of each tooth13, and nine first elongated-wall portions23(extended portions) which are extended upwardly from the first annular member21along the axial direction, and which are provided intermittently in the circumferential direction, and nine short-wall portions24each provided between the adjacent first elongated-wall portions23, and having a shorter dimension in the circumferential direction than that of the first elongated-wall portion23.

The second insulator30includes a second annular member31capable of covering the lower portion of the yoke12, nine second wind portions32each capable of covering the lower portion of each tooth13, and nine second wall portions33extended downwardly along the axial direction from the second annular member31.

A structure of the first elongated-wall portion23located at the outer-diameter side of the coil V1in the first insulator20will be described below.

With reference toFIG. 3A, the first elongated-wall portion23includes a first guide surface51(a guide surface) that guides three strings of the winding40in the circumferential direction, and a second guide surface52that guides a string of the winding40among the three strings in the inner-diameter direction.

Among the three strings of the winding40, the upper and lower two winding strings40and40are drawn out from the one coil among the coil U1to the coil W3(seeFIG. 1), and are two crossover strings41and42that are guided by the first guide surface51when directed toward the other coil. The winding40located between the crossover strings41and42is a wound string43which is drawn out from the one coil among the coil U1to the coil W3, is guided by the first guide surface51, is drawn in the inner-diameter direction from the second guide surface52, and forms the coil V1.

Provided at an upper end51aof the first guide surface51are a first protruding portion60and a second protruding portion70that protrude in the outer-diameter direction. A dimension of the first protruding portion60in the circumferential direction is, for example, substantially ⅓ of the dimension of the circumferential direction of the first guide surface51. A gap between the first protruding portion60and the second protruding portion70is, for example, substantially ⅓ of the dimension of the first guide surface51in the circumferential direction. Note that the number of the protruding portions may be one, or equal to or greater than three.

A first groove21ais formed in the annular member21below the first protruding portion60. A second groove21bis formed in the annular member21below the second protruding portion70.

With reference toFIG. 3AandFIG. 3B, the first protruding portion60includes a rectangular main-body portion61, and a convex portion62extended downwardly from a tip61aof the main-body portion61at the outer-diameter side. The main-body portion61and the convex portion62are formed together. A top surface60aof the first protruding portion60is located on the same plane as a top surface23aof the first elongated-wall portion23.

A bottom surface63of the first protruding portion60is an abutting surface capable of abutting the three strings of the winding40guided by the first guide surface51. The bottom surface63(abutting surface) is directed downwardly that is an opposite direction to the upper direction in which the first elongated-wall portion23is extended. More specifically, the bottom surface63includes a curved portion64that is curve so as to expand upwardly, and a flat-surface portion65that is located at the outer-diameter side relative to the curved portion64.

The curved portion64includes an external slant portion66(a slant portion) that goes downwardly toward the outer-diameter direction from a top point P, and an internal slant portion67that goes downwardly toward the inner-diameter direction from the top point P. The external slant portion66is a surface capable of abutting a semicircular portion40a(a half portion at the outer-diameter side) at the outer-diameter side in the winding40with a circular cross-sectional shape.

Note that the cross-sectional shape of the winding40is not limited to a circle, but may be polygonal. Moreover, as illustrated inFIG. 3B, the curved portion64may employs a structure that can hold the winding40from both sides, or a structure that retains therein the winding40without a contact to both ends of the winding40(unillustrated).

Furthermore, although the bottom surface63includes the two surfaces which are the curved portion64and the flat-surface portion65according to this embodiment, for example, the bottom surface may be a single flat surface that goes down downwardly toward the outer-diameter direction from the first guide surface51.

The second protruding portion70has the same dimension and shape as those of the first protruding portion60, and includes a bottom surface73capable of abutting the three strings of the winding40. The description for the other structures of the second protruding portion70will be omitted. The first protruding portions60and the second protruding portions70are also formed in the other respective first elongated-wall portions23illustrated inFIG. 1.

Next, advantageous effects of this embodiment will be described.

With reference toFIG. 3B, the first elongated-wall portion23includes the first protruding portion60that protrudes in the outer-diameter direction from the first guide surface51. The first protruding portion60includes the bottom surface63capable of abutting the three strings of the winding40that are guided by the first guide surface51. The bottom surface63includes the curved portion64and the flat-surface portion65. Accordingly, when the three strings of the winding40guided in the circumferential direction move upwardly, the winding40abuts the curved portion64or the flat-surface portion65.

In addition, the curved portion64includes the external slant portion66that goes down toward the outer-diameter direction from the top point P. The external slant portion66is a surface capable of abutting the semicircular portion40aof the winding40with the circular cross-sectional shape at the outer-diameter side. Hence, even if it the winding40moves in the outer-diameter direction, the winding40abuts the external slant portion66.

As described above, when the winding40moves not only upwardly but also in the outer-diameter direction, the winding40abuts the bottom surface63. This enables the winding40guided in the circumferential direction to be surely retained at the predetermined position.

Second Embodiment

With reference toFIG. 4AandFIG. 4B, next, a second embodiment will be described. In comparison with the first embodiment, first elongated-wall portions23A and terminals80are different according to the second embodiment.

A dimension of each first elongated-wall portion23A in the circumferential direction is greater than the dimension of each first elongated-wall portion23of first embodiment in the circumferential direction. More specifically, the dimension of the first elongated-wall portion23A in the circumferential direction is substantially equal to the dimension of a portion of the annular member21(seeFIG. 2) of the first insulator20divided into nine portions in the circumferential direction. The same structure as that of the first embodiment will be denoted by the same reference numeral, and the description thereof will be omitted.

Each first elongated-wall portion23A includes a first guide surface51A that guides two strings of the winding40in the circumferential direction, and a second guide surface52A and a third guide surface53A which are extended in the inner-diameter direction from both ends of the first guide surface51A, respectively. The second guide surface52A and the third guide surface53A are each a guide surface that guides the winding40in the inner-diameter direction.

The first guide surface51A includes a first protruding portion60(one protruding portion), and a second protruding portion70(another protruding portion). A string extended straightly in the two strings of the winding40guided by the first guide surface51A will be defined as a crossover string45, and a string which is partially curved and connected to a terminal80will be defined as a connection line46.

The terminal80is formed in a thin plate shape that has a thin dimension in the radial direction, and includes a rectangular main-body portion81, two insertion portions82which are extended downwardly from the lower portion of the main-body portion81, and which are inserted in a top surface23Aa of the first elongated-wall portion23A, and a fold-back portion83which is located between the two insertion portions82and which is folded back upwardly from the lower portion of the main-body portion61.

The fold-back portion83includes a holding portion84(a connection portion) that is electrically connected to the connection line46by holding the connection line46. An example connection scheme is fusing.

The connection line46abuts the bottom surface63of the first protruding portion60, the holding portion84, and the bottom surface73of the second protruding portion70. More specifically, the connection line46includes a first slant portion47that is obliquely extended from the first protruding portion60to the holding portion84, a parallel portion48that is extended in parallel with the top surface23Aa in the holding portion84, and a second slant portion49that is obliquely extended from the lower portion of the fold-back portion83to the second protruding portion70.

The holding portion84is located between, in the circumferential direction, the first protruding portion60and the second protruding portion70, and is offset toward the second protruding portion70. Note that the connection portion83is not limited to a case in which it is located within a region between the first protruding portion60and the second protruding portion70, but may be located so as to be out of such a region at the outer-diameter side or at the inner-diameter side.

According to the second embodiment, in addition to the advantageous effects of the first embodiment, the following advantageous effects are accomplishable.

The terminal80includes the holding portion84that is electrically connected to the connection line46. As viewed from the top of the motor stator10along the axial direction (seeFIG. 1), the holding portion84is located between the first protruding portion60and the second protruding portion70that adjoin to each other in the circumferential direction.

Accordingly, when the connection line46is connected to the holding portion84, by causing the winding40to abut the bottom surface63of the first protruding portion60, the connection line46can be bent with the first protruding portion60being as an origin. Since the bent portion of the connection line46is caught by the first protruding portion60, it becomes easy to put the connection line46across the holding portion84. Moreover, the winding drawn toward the second protruding portion70from the holding portion84is caught by the second protruding portion70. This facilitates subsequent works of guiding the connection line46in the circumferential direction and of drawing the winding in the inner-diameter direction.