Core for field element

CORE FOR FIELD ELEMENT

The present invention relates to a core for a field element, and more particularly to the shape of the core for a field element.

Conventionally, a technique for increasing the strength of a core for a magnetic field element has been proposed. For example, in Patent Document 1 below, a slot into which a field magnet is inserted is divided into two, and a connecting portion connecting the outer and inner peripheral sides of the core for a field element with respect to the slot (Patent Document 1) A technique for installing a "bridge") is disclosed.

However, since the divided slot of Patent Document 1 has a rectangular shape, a corner portion is formed in the portion to which the connecting portion is attached. For this reason, there existed a possibility that the stress which generate|occur|produces in the connection part was concentrated in the said corner part, and there existed a possibility that the connection part and, by extension, the core for field elements deform|transforms.

For example, the following patent document 2 and patent document 3 introduce the technique which relieves the concentration of stress by forming a round shape in the corner part of a connection part.

In addition, the technology related to the present invention is introduced in Patent Documents 4 and 5.

Patent Document 1: Japanese Utility Model Publication No. Hei 7-11859

Patent Document 2: Japanese Patent Application Laid-Open No. 2002-281700

Patent Document 3: Japanese Patent Application Laid-Open No. 2004-260888

Patent Document 4: Japanese Patent Application Laid-Open No. 9-294344

Patent Document 5: Japanese Patent Application Laid-Open No. 2003-174747

However, in Patent Document 2 and Patent Document 3, only a rounded shape is formed at the corner, and the other parts are flat. For this reason, stress still tends to concentrate in the vicinity of the corner where the round part was formed.

The present invention has been made in view of the circumstances described above, and an object of the present invention is to relieve stress concentration in a connecting portion.

A first aspect of the core for a magnetic field element according to the present invention is arranged in an annular shape in a circumferential direction 92 around a predetermined direction 91, and forms a pair adjacent to the circumferential direction, each of which is adjacent to the circumferential direction. The field magnet through-holes 41 and 42 having a pair of end portions 411, 412, 421, 422 in the direction are provided between the field magnet through-holes forming the same pair, and are respectively different through the field magnet through-holes a connecting portion (11; 17; 18) belonging to the hole and having the end portions (412, 422) adjacent to the circumferential direction as side surfaces (111, 112; 111, 112; 171, 172; 181, 182); At least one side (111; 111; 171; 181) of the side surface is a circle centered on the position (c111; c111; c171; c1811, c1812) on the side opposite to the connection part with respect to the side when viewed from the predetermined direction. following curved portion 111a ; 121a to 161a; 171a; 181a, 181c), and the length (Lm ; Ln ; ... The ratio (Rb/Lm; Rb/Ln; ...; Rb/Ln1, Rb/Ln2) of the radius Rb of the circle is 1.0 or more and 1.5 or less, and the tangent line t(r) of the curved portion viewed from the predetermined direction ) is along the extending direction 93 of the connecting portion only at any one position r13 ; r13 ; r33 ; r73 , r76 between both ends of the curved portion.

A second aspect of the core for a field element according to the present invention is the core for a field element according to the first aspect, and the field magnet through-holes 41 and 42 forming the same pair are all directed in the predetermined direction 91 . The boa extends along any one direction 94 defined for each pair.

A third aspect of the magnetic field element core according to the present invention is the magnetic field element core according to the first or second aspect, wherein the position r13 is the midpoint of the respective positions of the both ends r11 and r12.

A fourth aspect of the magnetic field element core according to the present invention is the magnetic field element core according to the first or second aspect, wherein the position r13 is from the midpoint of the respective positions of the both ends r11 and r12 to the both ends. out on either side.

A fifth aspect of the magnetic field element core according to the present invention is a magnetic field element core according to the first or second aspect that is rotatable about a rotational axis along the predetermined direction (91), the extension direction (93) is along a radial direction about the rotation axis as viewed from the predetermined direction 91 .

A sixth aspect of the magnetic field element core according to the present invention is the magnetic field element core according to any one of the first to fifth aspects, wherein the both ends r11, r12; r31 of the curved portion 111a; 171a; r32) is connected to the surfaces 21 and 31 of the field magnet through-holes 41 and 42 respectively located on the outer and inner peripheral sides with respect to the connecting portions 11 and 17.

A seventh aspect of the core for a magnetic field element according to the present invention is the core for a magnetic field element according to any one of the first to sixth aspects, and the side surface 111 viewed from the predetermined direction 91; With respect to 111 ; 181 , the side surface is in a direction 951 perpendicular to the direction 941 , 942 in which the field magnet through-holes 41 , 42 extend from the connecting portion 11 ; ...; 11 ; 11 ; 18 . , 952), further having a planar portion 121b; r71) is connected via the planar part to the surface 21;

An eighth aspect of the core for a field element according to the present invention is a core for a field element according to a seventh aspect, wherein the one (r51; r62) of the end of the curved portion (151a; 161a) is the flat portion (151b). ; 161b).

A ninth aspect of the core for a field element according to the present invention is a core for a field element according to a seventh aspect, wherein the planar portions 121b; ...; 141b; 181b viewed from the predetermined direction 91 are the field magnets. Through holes 41 , 42 protrude from the curved portions 121a ; 141a ; 181a along the directions 941 , 942 extending from the connecting portions 11 ; ; 11 ; 18 .

A tenth aspect of the magnetic field element core according to the present invention is the magnetic field element core according to any one of the seventh to ninth aspects, wherein the side surface 181 is the curved portion as viewed from the predetermined direction 91 . is provided in pairs 181a and 181c, and the flat portion 181b is provided between the curved portions.

According to any one of the first to third aspects of the core for a field element according to the present invention, the stress generated in the connecting portion is easily dispersed by providing the curved portion. Therefore, the stress concentration at the connecting portion is relieved.

According to the fourth aspect of the core for a field element according to the present invention, the angle between the tangent line at the end of the curved portion opposite to the direction deviating from the midpoint and the direction in which the field magnet through-hole extends from the connecting portion can be increased. have. Therefore, the stress concentration at the said edge part can be relieve|moderated.

According to the fifth aspect of the core for a field element according to the present invention, since the stress generated in the connecting portion is generated along the extending direction of the connecting portion, deformation of the connecting portion can be prevented.

According to the sixth aspect of the core for a field element according to the present invention, since the entire side surface is curved, stress concentration is unlikely to occur in the connecting portion.

According to any one of the seventh to ninth aspects of the core for a field element according to the present invention, in the curved portion, stress generated in the connecting portion can be dispersed. In addition, by providing the curved portion on the side surface, it is possible to provide the flat portion without narrowing the area viewed from the predetermined direction of the field magnet through hole. And when a magnet is inserted in the field magnet through-hole, the said magnet can be fixed in the flat part.

According to the tenth aspect of the core for a field element which concerns on this invention, the stress which generate|occur|produces in the connection part in the 1st and 2nd curved part can be disperse|distributed. In addition, when a magnet is inserted into the field magnet through-hole, the magnet can be fixed in a flat portion. And even when the end face of the magnet on the connecting portion side is convexly curved, the flat part can be provided corresponding to the end face.

The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings.

Fig. 1 is a top view conceptually showing a core 1 for a field element according to the present invention.

Fig. 2 is a diagram conceptually showing the connecting portion 11 described in the first embodiment.

Fig. 3 is a diagram conceptually showing the connecting portion 11 described in the first embodiment.

4 is a diagram showing the relationship between the angle θb and the maximum value of the stress generated in the connecting portion 11. As shown in FIG.

Fig. 5 is a view showing a gap 431 provided in the magnetic field magnet through-holes 41 and 42. As shown in Figs.

6 is a diagram showing the relationship between the angle θb and the maximum value of the stress generated in the connecting portion 11. As shown in FIG.

Fig. 7 is a view showing a gap 432 provided in the field magnet through-holes 41 and 42. As shown in Figs.

Fig. 8 is a view showing a gap 43 provided in the field magnet through-holes 41 and 42;

Fig. 9 is a view showing a gap 43 provided in the field magnet through-holes 41 and 42;

Fig. 10 is a view showing a gap 43 provided in the field magnet through-holes 41 and 42;

Fig. 11 is a diagram conceptually showing the connecting portion 11 described in the second embodiment.

Fig. 12 is a diagram conceptually showing the connecting portion 11 described in the second embodiment.

Fig. 13 is a diagram conceptually showing the connecting portion 11 described in the second embodiment.

Fig. 14 is a diagram conceptually showing the connecting portion 11 described in the second embodiment.

Fig. 15 is a diagram conceptually showing the connecting portion 11 described in the second embodiment.

FIG. 16 is a diagram showing the stress generated in the connection part 11 shown in FIG. 13 as a contour line.

Fig. 17 is a view showing stress generated in a connecting portion showing a shape different from that of the connecting portion 11;

Fig. 18 is a view showing the stress generated in the connecting portion showing a shape different from that of the connecting portion 11. As shown in Figs.

Fig. 19 is an enlarged view of an area surrounded by broken lines in Figs. 16 and 18;

Fig. 20 is a diagram conceptually showing the connecting portion 17 described in the third embodiment.

Fig. 21 is a diagram conceptually showing a connecting portion 17 described in the fourth embodiment.

22 is a diagram showing the stress generated in the connecting portion 18 as a contour line.

Fig. 23 is a view showing stress generated in a connecting portion having a shape different from that of the connecting portion 18;

24 is a diagram conceptually showing the position of the caulking 9. As shown in FIG.

Fig. 25 is a diagram conceptually showing the position of the caulking 9;

Fig. 1 is a top view conceptually showing a core 1 for a field element according to the present invention. The core 1 for a field element includes field magnet through-holes 41 and 42 and a connecting portion 11 (connecting portions 17 and 18 in the third and fourth embodiments described later, respectively).

The field magnet through-holes 41 and 42 are arranged in an annular shape in the circumferential direction 92 around the predetermined direction 91 , and are paired adjacent to the circumferential direction 92 . In Fig. 1, the case where the field magnet through-holes 41 and 42 forming the same pair extend along an arbitrary one direction 94 determined for each pair as viewed from the predetermined direction 91 is shown. However, as viewed from the predetermined direction 91, either one of the field magnet through-holes 41 and 42 forming the same pair may be inclined with respect to the other. Specifically, the direction 941 in which the field magnet through-hole 41 extends and the direction 942 in which the field magnet 42 extends may cross each other. In the embodiment described later, a case will be described in which all of the field magnet through-holes 41 and 42 follow one direction 94 .

The field magnet through-hole 41 has a pair of end portions 411 and 412 in the circumferential direction 92 , and the field magnet through-hole 42 has a pair of end portions 421 and 422 in the circumferential direction 92 , respectively. have

The connecting portion 11 is provided between the field magnet through-holes 41 and 42 forming the same pair, and has end portions 412 and 422 as side surfaces 111 and 112, respectively. These contents belong to different field magnet through-holes 41 and 42, respectively, so that the ends 412 and 422 adjacent to the circumferential direction 92 constitute the side surfaces 111 and 112 of the connecting portion 11, respectively. have.

Hereinafter, the shapes of the side surfaces 111 and 112 of the connection part 11 will be described. In Fig. 1, reference numeral 2 is given to the core part on the outer periphery side with respect to the field magnet through-holes 41 and 42 and the connection part 11 for the core 1 for the field element, and code 3 is given to the core part on the inner periphery side. are doing

<First embodiment>

2 and 3 are enlarged views of one of the connecting portions 11 shown in FIG. 1 . The side surfaces 111 and 112 of the connecting portion 11 are curved concavely. Specifically, when viewed from the predetermined direction 91 , the tangent [t(r13)] of the side surface 111 only at one position r13 between the both ends of the side surface 111 corresponds to the extension direction ( 93). In addition, the extension direction 93 is a direction from the outer peripheral side to the inner peripheral side of the core 1 for field elements, and is perpendicular|vertical with respect to the one direction 94 in this embodiment.

The side surface 112 is similarly curved concavely, and the tangent line t(r16) follows the extension direction 93 only at one position r16 between the both ends r14 and r15.

According to the shape of the side surfaces 111 and 112 described above, since all of the side surfaces 111 and 112 are curved, the stress generated in the connection part 11 is dispersed, and thus stress concentration does not occur in the connection part 11 .

In addition, if the whole of the side surfaces 111 and 112 is grasped as the curved portions 111a and 112a, the shape of the above-described side surfaces 111 and 112 can be grasped as follows. That is, both ends of the curved portion 111a viewed from the predetermined direction 91 have a surface 21 on the core portion 2 side and a surface 31 on the core portion 3 side of the field magnet through hole 41, respectively. is connected to The curved part 112a can be grasped|ascertained similarly.

From the viewpoint of dispersion of stress, it is preferable that the straight line A1 including the positions r13 and r16 follows one direction 94 .

In particular, the case where the straight line A1 coincides with the center line A0 along one direction 94 of the field magnet through-holes 41 and 42 seen from the predetermined direction 91 is shown in FIG. That is, the position r13 is at the midpoint of the respective positions of the both ends r11 and r12 of the side surface 111 . Further, the position r16 is at the midpoint of the respective positions of the both ends r14 and r15 of the side surface 112 .

Also, Fig. 3 shows a case in which the straight line A1 deviates from the center line A0 toward the core portion 2 side. That is, the position r13 is deviated to the core portion 2 side, that is, to the position r11 side with respect to the midpoint of the respective positions of the both ends r11 and r12 of the side surface 111 . Further, the position r16 is deviated toward the core portion 2 side, that is, the position r14 side, with respect to the midpoint of the respective positions of the both ends r14 and r15 of the side surface 112 .

According to this shape, the positions r13 and r16 are on the opposite side to the direction deviating from the midpoint (the straight line A1 may be regarded as the opposite side to the direction deviating from the center line A0), that is, in Fig. 3, the core portion 3 The angle between the tangent line t(r12) of the side surface 111 at the end r12 of the side surface 111 and the surface 31 of the field magnet through-hole 41 on the field magnet through-hole 41 side As ?1 becomes large, stress concentration at the end r12 is relieved. Similarly, at the end r15 of the side surface 112 , the angle between the tangent line t(r15) of the side surface 112 and the surface 31 of the field magnet through-hole 42 on the field magnet through-hole 42 side. As θ1 becomes large, the stress concentration at the end r15 is relieved.

For example, the straight line A1 may deviate to the core portion 3 side with respect to the center line A0. That is, the positions r13 and r16 may deviate to the core portion 3 side with respect to the midpoint.

From the viewpoint of dispersion of stress in any of the above-described shapes, the side surfaces 111 and 112 viewed from the predetermined direction 91 are on a straight line A1 on the side opposite to the connecting portion 11 with respect to the side surfaces 111 and 112, respectively. It is more preferable to follow a circle centered on the positions c111 and c112 at 2 and 3 show this case.

4 shows an angle θb between the tangent line [t(r11)] and the surface 21 on the field magnet through-hole 41 side in the shape of the connection portion 11 shown in FIG. 2, and occurs at the connection portion 11 The relationship between the maximum values of the stresses to be applied is shown in a graph. Incidentally, the angle between the tangent line t(14) and the surface 21 on the field magnet through-hole 42 side is equal to the angle θb.

The angle θb is expressed by Equation (1) using the ratio (Rb/Lm) of the radius Rb of the circle along the sides 111 and 112 to the width Lm. In addition, the width Lm is a length with respect to a direction 95 perpendicular to one direction 94 of the field magnet through-holes 41 and 42 . In addition, the one direction 94 can be grasped|ascertained as the direction in which each of the field magnet through-holes 41 and 42 extend from the connection part 11, and it is the same below.

<maths num="1"><df><img file="KR20080098685A_D0001.tif" /> … (1)</df></maths>

The graph shown in FIG. 4 is a simulation result under the following conditions. That is, the outer diameter of the core 1 for a field element is 88.6 (mm), the rotation speed is 120 (/min), the distance Lb between the position r13 and the position r16 is 0.6 (mm), and the width Lm is 2.8 (mm), the radius Rb is 1.4 to 6.7 (mm), that is, the angle θb is 100 to 180 (°). In addition, as shown in Fig. 5, a gap 431 is provided at each end 411, 421 of the field magnet through-holes 41, 42. The gap 431 extends from the ends 411 and 421 to the outer peripheral side of the core 1 for the field element. In addition, in the simulation, a round shape having a radius of 0.2 (mm) was formed at each of the ends r11, r12, r14, and r15.

From the graph shown in Fig. 4, when the angle θb is in the range of 106.1 to 135.6 (°), that is, when the ratio (Rb/Lm) is in the range of 0.7 to 1.8, the maximum value of the stress is 120 (MPa) or less. it can be seen that Further, it can be seen that the maximum value of the stress is 115 (MPa) or less when the angle θb is in the range of 109.5 to 120 (°), that is, when the ratio (Rb/Lm) is in the range of 1.0 to 1.5.

Fig. 6 is a simulation result obtained by changing the conditions from the graph shown in Fig. 4; The conditions are as follows. The outer diameter of the core 1 for a magnetic field element is 123 (mm), the rotation speed is 120 (/min), the distance Lb is 0.7 (mm), the width Lm is 5.2 (mm), and the radius Rb is 2.6 to 2.6 to 10.4 (mm), that is, the angle θb is 104-180 (°). Further, as shown in Fig. 7, a gap 432 is provided at each end 411, 421 of the field magnet through-holes 41, 42. The gap 432 extends from the ends 411 and 421 between the core 1 for the field element and the outer periphery of the core 1 for the field element. In addition, in the simulation, a round shape having a radius of 0.2 (mm) was formed at each of the ends r11, r12, r14, and r15.

From the graph shown in Fig. 6, it can be seen that the maximum value of the stress is 100 (MPa) or less when the angle θb is in the range of 110 to 180 (°).

The ends 411 and 412 may be provided with a space|gap 43 which shows the shape shown in FIGS. 8-10, for example. In Fig. 8, the air gap 43 extends from the ends 411 and 421 to the outer periphery of the core 1 for the field element and is enlarged toward the outer periphery. In Fig. 9, the gap 43 extends from the ends 411 and 421 between the field magnet through-holes 41 and 42 and the outer periphery. Therefore, it becomes narrower. In Fig. 10, the gap 43 includes a portion 43a extending outwardly from the ends 411 and 421, and a portion 43b spaced apart from the portion and provided between the field magnet through-holes 41 and 42 and the outer periphery. has

&lt;Second embodiment&gt;

11 to 15, respectively, with respect to the connecting portion 11 shown in FIG. 2, the side surfaces 111 and 112 of which are planar portions along the direction 95 perpendicular to the one direction 94 (hereinafter referred to as "planar portions"). ) (121b, 131b, 141b, 151b, 161b, 122b, 132b, 142b, 152b, 162b) is shown. In this case, the side surfaces 111 and 112 have curved portions 121a, 131a, 141a, 151a, 161a, 122a, 132a, 142a, 152a, 162a in addition to the flat portions 121b, 131b, 141b, 151b, and 161b. As described in the first embodiment, when the one direction 94 is grasped in the direction in which each of the field magnet through-holes 41 and 42 extend from the connecting portion 11, the planar portions 121b, 131b, 141b, 151b, 161b , 122b, 132b, 142b, 152b, 162b) can be understood to follow a direction perpendicular to the direction.

In Fig. 11, planar portions 121b and 122b are provided at the end portions of the side surfaces 111 and 112 on the core portion 2 side, respectively. The flat portion 121b protrudes from the curved portion 121a along one direction 94 . The planar portion 122b protrudes from the curved portion 122a along one direction 94 .

In addition, the planar parts 121b and 122b may be provided at the edge part of the core part 3 side of the side surfaces 111 and 112, respectively.

In Fig. 12, a flat portion 131b is provided at an end of the side surface 111 on the core portion 2 side, and a flat portion 132b is provided at an end portion of the side surface 112 on the core portion 3 side. The flat portion 131b protrudes from the curved portion 131a along one direction 94 . The planar portion 132b protrudes from the curved portion 132a along one direction 94 .

In Fig. 13, flat portions 141b are provided at both ends of the side surface 111, and flat portions 142b are provided at both ends of the side surface 112, respectively. The flat portion 141b protrudes from the curved portion 141a along one direction 94 . The flat portion 142b protrudes from the curved portion 142a along one direction 94 .

In Fig. 14, flat portions 151b are provided at both ends of the side surface 111, and planar portions 152b are provided at both ends of the side surface 112, respectively. The curved portion 151a is directly connected to the planar portion 151b. The curved portion 152a is directly connected to the planar portion 152b.

In Fig. 15, planar portions 161b and 162b are provided at the end portions of the side surfaces 111 and 112 on the core portion 3 side, respectively. The curved portions 161a and 162a are directly connected to the planar portions 161b and 162b, respectively.

In addition, the planar parts 161b, 162b may be provided in the edge part of the core part 2 side of the side surfaces 111 and 112, respectively.

The shape of these side surfaces 111 can be grasped as follows. That is, at least one of the ends r21, r23, r41, r42, r51, r52, r62 of the curved portions 121a, 131a, 141a, 151a, 161a viewed from the predetermined direction 91 is the flat portion 121b, 131b. , 141b, 151b, 161b) to the surfaces 21 and 31 of the field magnet through-hole 41 on the same side as the end with respect to the curved portions 121a, 131a, 141a, 151a, 161a. The side 112 can be grasped similarly.

According to the shape of the above-described side surfaces (111, 112), the curved portions (121a, 131a, 141a, 151a, 161a, 122a, 132a, 142a, 152a, 162a), the stress generated in the connection portion (11) can be dispersed have. Furthermore, by providing the curved portions 121a, 131a, 141a, 151a, 161a, 122a, 132a, 142a, 152a, 162a on the side surfaces 111 and 112, the area viewed from the predetermined direction 91 of the field magnet through-hole The planar portions 121b, 131b, 141b, 151b, 161b, 122b, 132b, 142b, 152b, and 162b can be installed without narrowing the . And when a magnet is inserted in the field magnet through-holes 41 and 42, the said magnet can be fixed in the flat part.

In the first embodiment, by setting the ratio (Rb/Lm) in the range of 1.0 to 1.5, the result that the maximum value of the stress decreases was obtained by simulation. The width Lm may be viewed as the length Ln with respect to the vertical direction 95 of the curved portion of the side surface 111 . Therefore, it can be assumed that the same result is obtained even if the length Ln with respect to the direction perpendicular to the width Lm of the curved portions 121a, 131a, 141a, 151a, 161a, 122a, 132a, 142a, 152a, 162a is adopted. can

Fig. 16 shows the results obtained by simulation of the stress generated in the connecting portion 11 shown in Fig. 13 by contour lines 701 to 703. As shown in Figs. Contours 701 to 703 represent large stresses in this order.

The conditions of the simulation were that the outer diameter of the core 1 for the field element 1 was 90 (mm), the rotation speed was 120 (/min), the distance Lb between the positions r13 and r16 was 0.6 (mm), and the width ( Lm) is 2.8 (mm), length Ln is 1.8 (mm), radius Rb is 2.3 (mm), and ratio (Ln/Rb) is 0.78.

It can be seen from FIG. 16 that the stress is maximized at the center of the curved portions 141a and 142a with respect to the direction 95 perpendicular to the one direction 94 . The stress in this part was about 120 (MPa).

17 and 18 are results obtained by simulation for a connection portion exhibiting a shape different from that shown in FIG. 13 for comparison with the result shown in FIG. In Fig. 17, the result of flattening the curved portion with respect to the connecting portion 111 (this portion is referred to as "flat portion 201" here) is shown by the stress contour lines 711 to 714. Contours 711 - 714 represent large stresses in this order. In addition, the thickness of the flat portion 201 of the connecting portion in one direction 94 is 0.6 (mm), and the other conditions are the same as those of FIG. 16 . In Fig. 18, contour lines 721 to 724 show the result of forming a round shape with a radius of 0.5 (mm) at both ends of the flat portion 201 for the connecting portion shown in Fig. 17 . Contours 721 - 724 represent the largest stresses in this order. Other conditions are the same as those for FIG. 16 .

It can be seen from FIG. 17 that stress is concentrated at both ends of the flat portion 201 . The stress in this part was about 139 (MPa). It can be seen from Fig. 18 that the stress is concentrated in the vicinity of the portion where the round portion and the flat portion 201 are connected. The stress in this part was about 130 (MPa).

From the above results, it can be seen that by providing the curved portion 141a on the side surface 111 , the stress concentration of the connecting portion 111 is relieved even when the flat portions 141b and 142b are provided at both ends thereof. Moreover, since the distance between the position r13 and the position r16 becomes small, the short circuit of the magnetic flux is prevented.

Figs. 19A and 19B show enlarged regions surrounded by broken lines shown in Figs. 16 and 18, respectively. It can be seen from Fig. 19(a) that the stress generated at the corner on the curved portion 141a side of the flat portion 141b is small. In addition, the area of the region where the stress is small (the region surrounded by the contour line 701 and the side surface 111) is larger than the area of the region surrounded by the contour line 721 and the side surface shown in Fig. 19B. That is, it turns out that when the flat part 201 shown in FIG. 18 is curved like the curved parts 141a, 142a (FIG. 16), it becomes difficult to concentrate stress at the said corner.

&lt;Third embodiment&gt;

20 is a case in which the extending direction 93 of the connecting portion 11 shown in FIG. 2 is inclined with respect to the direction 95 perpendicular to the one direction 94 when viewed from the predetermined direction 91, the connecting portion ( 17) is shown. In addition, reference numerals 171 and 172 are attached to the side surface of the connecting portion 17 . For example, when the respective extension directions 941 and 942 (Fig. 1) of the field magnet through-holes 41 and 42 intersect, the extension direction 941 and the extension direction 942 are the cores ( 1) The connecting portion 17 is inclined with respect to the direction to bisect the angle formed on the inner peripheral side.

Specifically, in the case where the connecting portion 17 is provided at a position where the radial direction about the rotational axis of the magnetic field element core 1 is inclined with respect to the direction 95 perpendicular to the one direction 94, the connecting portion The extension direction 93 of (17) is along the radial direction.

As seen from the predetermined direction 91 with respect to the side surface 171, only at one position r33 between the both ends r31 and r32 of the side surface 171, the tangent line [t(r33)] of the side surface 171 is a connecting portion along the direction of extension 93 of (17). Also, similarly to the side surface 172 , a tangent line [t(r36)] to the side surface 172 only at one position r36 between the both ends r34 and r35 of the side surface 172 is the extension direction 93 . follow

According to this shape, deformation of the connecting portion 17 can be prevented. This is because, when the core 1 for the field element is rotated around the rotational axis along the predetermined direction 91, stress is generated in the core 1 for the field element in the radial direction about the rotational axis, but the connecting portion 17 ) is because the component of the stress in the direction perpendicular to the extension direction 93 becomes small because the extension direction 93 follows the direction in which the stress occurs.

From the viewpoint of dispersion of the stress, it is preferable that the straight line A2 including the positions r33 and r36 and the extension direction 93 of the connecting portion 17 are orthogonal to each other. In addition, the side surfaces 171 and 172 viewed from the predetermined direction 91 are centered on the positions c171 and c172 on the straight line A2 on the opposite side to the connecting portion 17 with respect to the side surfaces 171 and 172, respectively. It is more preferable to follow a circle.

Also about the connection part 17 which concerns on this embodiment, a flat part can be provided similarly to 2nd Embodiment.

&lt;Fourth embodiment&gt;

Fig. 21 conceptually shows the connecting portion 18 according to the present embodiment. In addition, reference numerals 181 and 182 are attached to the side surface of the connecting portion 18 . In this embodiment, the extending direction 93 of the connecting portion 18 is perpendicular to the one direction 94 .

The side surface 181 has curved portions 181a and 181c and a planar portion 181b. The curved portion 181a viewed from the predetermined direction 91 is curved concavely, and the tangent [t(r73)] is formed only at one position r73 between the both ends r71 and r72 of the curved portion 181a. along the direction of extension 93 .

The curved portion 181c is also curved concavely in the same manner as the curved portion 181a, and the tangent [t(r76)] extends in the direction of extension 93 only at one position r76 between the both ends r74 and r75. follow

The planar portion 181b is flat along a direction 95 perpendicular to the one direction 94 and is provided between the curved portion 181a and the curved portion 181c. Further, as described in the first embodiment, when one direction 94 is grasped as a direction in which each of the field magnet through-holes 41 and 42 extends from the connecting portion 18, the planar portion 181b is perpendicular to the direction. It can be seen that the human direction is followed.

The flat portion 181b may protrude with respect to the curved portions 181a, 181c along one direction 94, and the ends r71 and r75 of the curved portions 181a, 181c may be directly connected to the flat portion 181b. . Also, the shape of the former is shown in FIG.

Side 182 has curved portions 182a and 182c and planar portions 182b. The curved portion 182a viewed from the predetermined direction is curved concavely, and the tangent line [t(r79)] extends in the extension direction ( 93).

The curved portion 182c is similarly curved concavely, and the tangent line t(r82) follows the extension direction 93 only at one position r82 between the both ends r80 and r81.

The planar portion 182b is flat along a direction 95 perpendicular to the one direction 94 and is provided between the curved portion 182a and the curved portion 182c. In addition, the planar part 182b can be grasped|ascertained similarly to the planar part 181b.

The flat portion 182b may protrude with respect to the curved portions 182a, 182c along one direction 94, and the ends r77, r81 of the curved portions 182a, 182c may be directly connected to the flat portion 182b. . Also, the shape of the former is shown in FIG.

According to the above-described shape of the side surface 181 , the stress generated in the connecting portion 18 in the curved portions 181a and 181c can be dispersed. In addition, when a magnet is inserted into the field magnet through-hole 41, the magnet can be fixed by the flat portion 181b. Also, even when the end face of the magnet on the side of the connecting portion 18 is convexly curved, the flat portions 181b and 182b can be provided corresponding to the end face. The stress can be similarly distributed to the side surface 182 , and the magnet inserted into the field magnet through-hole 42 can be fixed.

From the viewpoint of dispersion of stress, the straight line A31 including the positions r73 and r79 is preferably orthogonal to the extension direction 93 . In addition, from the same viewpoint, it is preferable that the straight line A32 including the positions r76 and r82 is also orthogonal to the extension direction 93 . In addition, it is preferable that the length at which the planar portions 181b and 182b protrude from the curved portions 181a and 182a, respectively, is 1/3 or less with respect to the width Lm.

Further, the curved portions 181a and 182a viewed from the predetermined direction 91 are centered on the positions c1811 and c1821 on the straight line A31 on the opposite side to the connecting portion 18 with respect to the curved portions 181a and 182a, respectively. It is more preferable to follow a circle with Also, for the curved portions 181c and 182c viewed from the predetermined direction 91, the positions c1812 and c1822 on the straight line A32 on the opposite side to the connecting portion 18 with respect to the curved portions 181c and 182c, respectively. It is more preferable to follow the center circle.

When the radius of the circle centered on the positions c1811 and c1821 and the radius of the circle centered on the positions c1812 and c1822 are equal (hereinafter referred to as "radius Rb"), the first embodiment From the simulation results described above, the same assumptions as in the third embodiment can be made. That is, the ratio (Rb/Ln1) of the radius (Rb) to the length (Ln1) in the direction (95) perpendicular to one direction (94) of the curved parts (181a, 182a) is set in the range of 1.0 to 1.5, By setting the ratio Rb/Ln2 of the radius Rb to the length Ln2 in the direction 95 of the curved portions 181c and 182c in the range of 1.0 to 1.5, the maximum value of the stress is lowered.

Fig. 22 shows the results obtained by simulation of the stress generated in the connecting portion 18 shown in Fig. 21 by contour lines 731 to 735. As shown in Figs. Contours 731 to 735 represent the largest stresses in this order.

The conditions of the simulation were that the outer diameter of the core 1 for the field element 1 was 88.6 (mm), the rotation speed was 120 (/min), the distance Lb1 between the position r73 and the position r79 was 0.6 (mm), and the position ( The distance Lb2 between r76) and the position r82 is 0.6 (mm), the width Lm is 2.8 (mm), the lengths Ln1 and Ln2 are 1.15 (mm), and the radius Rb is 1.4 (mm). , the ratio (Rb/Ln1, Rb/Ln2) is 1.22, respectively. Further, a round shape having a radius of 0.2 (mm) was formed at both ends of each of the curved portions 181a, 181c, 182a, and 182c.

It can be seen from Fig. 22 that the stress is maximized at the center of the curved portions 181a, 181c, 182a, 182c with respect to the direction 95 perpendicular to the one direction 94. As shown in Figs. The stress in this part was about 123 (MPa).

Fig. 23 shows, for comparison with the result shown in Fig. 22, results obtained by simulation for a connecting portion showing a shape different from that shown in Fig. 21 by contour lines 741 to 746. As shown in Figs. The contour lines 741 to 746 grow in this order. The connecting portion flattens all of the connecting portions 181a, 181c, 182a, 182c (these portions are referred to as "flat portion 202"), and both ends of the flat portion 202 are round with a radius of 0.3 (mm). Represents a shape that has formed a shape.

It can be seen from Fig. 23 that stress is concentrated at both ends of each of the flat portions 202. As shown in Figs. The stress in this part is on the order of 140 (MPa).

From the above results, it can be seen that by providing the curved portions 181a, 181c, 182a, 182c on the side surface 181, the stress concentration is relieved compared to the connection portion (Fig. 23) where these portions are flat.

In any of the embodiments described above, when the respective extension directions 941 and 942 of the field magnet through-holes 41 and 42 intersect, the side surfaces 111 and 181 on the field magnet through-hole 41 side As for the base material, the "direction 95 perpendicular to the one direction 94" is the "direction 951 perpendicular to the extension direction 941 (FIG. 1)", the side surface 112 on the field magnet through hole 42 side 182), "direction 95 perpendicular to one direction 94" is replaced with "direction 952 perpendicular to extension direction 942 (FIG. 1)" and applied.

transform :

In any of the above-described embodiments, it is also applicable to three or more field magnet through-holes forming a set adjacent to the circumferential direction 92 . That is, any one of the connecting portions 11, 17 and 18 is employed between the field magnet through-holes which belong to the same set and which are adjacent to each other.

For example, the core 1 for a magnetic field element can be obtained by laminating|stacking electrical steel sheets in the predetermined direction 91, and caulking each electrical steel sheet with each other.

24 and 25 conceptually show the position of the caulking 9 . In Fig. 24, caulking 9 is provided on both sides with respect to the extending direction 93 of the connecting portions 11, 17, 18. Since it is difficult for the magnetic flux to short-circuit the connecting portions 11, 17, 18, the connecting portions 11, 17, 18 are liable to magnetically saturate. Therefore, the magnetic flux is hardly changed on the both sides of the connecting portions 11, 17, 18, and therefore the installation of the caulking 9 is desired.

In Fig. 25, in the vicinity of the center of the field magnet through-holes 41 and 42 with respect to one direction 94, caulking 9 is provided in each of the core portions 2 and 3; Thereby, the intensity|strength of the part on the side of the space|gap 43 with respect to the part whose intensity|strength is weak compared with the vicinity of the connection parts 11, 17, 18, ie, the connection part 11, 17, 18 increases.

Further, even if the core 1 for a magnetic field element is obtained by stacking electrical steel sheets in a predetermined direction 91, sandwiching them between the end plates from both sides in the predetermined direction 91, and fixing the whole with pins or bolts. good.

1 schematically shows the location of the hole 6 for installing the pin or bolt. In Fig. 1, with respect to the field magnet through-holes 41 and 42, on the inner peripheral side of the core 1 for the field element, a hole 6 is provided between the field magnet through-holes 41 and 42 which belong to different pairs and which are adjacent to each other. This is provided. Accordingly, when the balance weight is attached to the pin or bolt, even if the centrifugal force applied to the balance weight is transmitted to the pin or bolt, it is difficult to deform the core 1 for the field element.

Although the present invention has been described in detail, the foregoing description is illustrative in all respects, and the present invention is not limited thereto. It should be understood that numerous modifications not illustrated can be made without departing from the scope of the present invention.