Stator manufacturing method

Abstract

This stator manufacturing method is a method for manufacturing a stator comprising an annular stator core having a virtual axis that is a virtual axis as an axis, a plurality of slots provided in the stator core, and conductors arranged side by side in each of the slots. The conductor is inserted into the slot of the stator core in which the virtual axis is substantially horizontal.

Description

Stator manufacturing method

[0001] The present invention relates to a method for manufacturing a stator.

[0002] Various methods for manufacturing stators that constitute rotating electric machines have been devised. Patent Document 1 discloses an insulating coil end spacer that is either a band-shaped flat plate or a ring-shaped band plate and has a main wall portion that forms both front and back surfaces, and that further includes at least one of the following three components: protrusions that protrude from multiple locations on one edge of the main wall portion at predetermined intervals in a tooth-like pattern and form recessed slits between them; a number of first partition ridges that protrude from one of the front and back surfaces of the main wall portion at predetermined intervals, extend at a predetermined angle relative to the extension direction of the main wall portion, and form one of the guide grooves between them; and a number of second partition ridges that protrude from the other of the front and back surfaces of the main wall portion at predetermined intervals, extend at a predetermined angle in the opposite direction to the first partition ridges with respect to the extension direction of the main wall portion, and form the other of the guide grooves between them.

[0003] Japanese Patent Application Laid-Open No. 2004-032964

[0004] In the invention described in Patent Document 1, there is room for improvement in the method of manufacturing the stator.

[0005] A method for manufacturing a stator according to a first aspect of the present invention is a method for manufacturing a stator comprising: a ring-shaped stator core having an imaginary axis as its axis; a plurality of slots provided in the stator core; and conductors arranged side by side in each of the slots, wherein the conductors are inserted into the slots of the stator core, with the imaginary axis being approximately horizontal.

[0006] According to the present invention, a highly accurate stator 1 can be easily manufactured.

[0007] FIG. 1 shows an L-shaped coil in a slot. FIG. 2 shows a first state. FIG. 3 shows a holding element. FIG. 4 shows a second state. FIG. 5 shows a first comparative manufacturing method. FIG. 6 shows a second comparative manufacturing method. FIG. 7 shows an L-shaped coil in a slot in modified example 1.

[0008] -Embodiment- Hereinafter, an embodiment of a method for manufacturing a stator will be described with reference to FIGS.

[0009] FIG. 1 is an external view of a stator 1. In this embodiment, mutually orthogonal X, Y, and Z axes are also shown to clearly show the correlation between the drawings. The stator 1 includes a stator core 2, a plurality of slots 3 provided in the stator core 2, and stator conductors 4 arranged in each of the slots 3. The stator conductors 4 are formed by combining a number of L-shaped coils 400, which will be described later. The L-shaped coils 400 are also called "conductors." The stator core 2 has a substantially cylindrical shape, and this substantially cylindrical shape has an axis (hereinafter referred to as a "virtual axis") parallel to the Z axis. Each slot 3 is a groove formed inside the stator core 2 and parallel to the Z axis. The slots 3 are formed at equal intervals on the circumference of a circle centered on the virtual axis.

[0010] The stator conductors 4 are arranged parallel to the Z-axis along the slots 3 inside the stator core 2, but there are also regions outside the stator core 2 that are not parallel to the Z-axis. The stator conductors 4 shown in FIG. 1 are arranged on the circumference of two circles of different diameters centered on an imaginary axis, forming a double circle, so to speak. However, there is no particular limit to the number of overlaps between these circles, and they may be single circles with no overlap, or may have three or more overlaps. The stator conductors 4 are composed of a first conductor group 41 and a second conductor group 42.

[0011] FIG. 2 is a schematic diagram showing a manufacturing method of the stator 1. Hereinafter, the upper part of FIG. 2 will be referred to as the first state, the middle part of FIG. 2 as the second state, and the lower part of FIG. 2 as the third state. First, there is the first state, then the second state, and then the third state. The posture of the stator 1 is the same in all figures, and as shown in the lower left of FIG. 2, the upper side of the figure is the positive direction of the Y axis. Furthermore, the circled G and arrows shown adjacent to the X, Y, and Z axes indicate the direction of gravitational acceleration. That is, in FIG. 2, the negative Y axis direction is the direction of gravity, and the XZ plane is a substantially horizontal plane.

[0012] First, as shown in the upper part of Fig. 2, the stator core 2 is arranged approximately horizontally, and L-shaped coils 400, which are conductors, are arranged on both the positive side and the negative side of the Z axis. The L-shaped coil 400 has an inclined portion 401 and a leg portion 402. The inclined portion 401 and the leg portion 402 are each approximately straight, and the inclined portion 401 is inclined with respect to the leg portion 402. The end of the inclined portion 401 that is not connected to the leg portion 402 is called the inclined end portion 401E, and the end of the leg 402 that is not connected to the inclined portion 401 is called the leg end portion 402E.

[0013] In the following description, for convenience, the L-shaped coils 400 arranged on the negative side of the Z axis of the stator core 2 will be referred to as the first conductor group 41, and the L-shaped coils 400 arranged on the positive side of the Z axis of the stator core 2 will be referred to as the second conductor group 42. In Fig. 2, the first conductor group 41 and the second conductor group 42 are distinguished by solid and dashed lines.

[0014] The first conductor group 41 is held by a first jig 81. The first jig 81 holds the legs 402 of each of the L-shaped coils 400 belonging to the first conductor group 41. The second conductor group 42 is held by a second jig 82. The second jig 82 holds the legs 402 of each of the L-shaped coils 400 belonging to the second conductor group 42. The configurations of the first jig 81 and the second jig 82 will be described later.

[0015] The first conductor group 41 is moved in the positive direction of the Z axis using a first jig 81 while maintaining its cylindrical shape, and the second conductor group 42 is moved in the negative direction of the Z axis using a second jig 82 while maintaining its cylindrical shape. The legs 402 of the first conductor group 41 and the second conductor group 42 are inserted into the slots 3. The first conductor group 41 and the second conductor group 42 are inserted alternately into adjacent slots 3.

[0016] 2, the first conductor group 41 and the second conductor group 42 overlap in the Z-axis direction, in other words, in the XY plane, and the first jig 81 and the second jigs 82 are removed. In other words, as shown in the middle of Fig. 2, when the distance L, which is the overlap between the first conductor group 41 and the second conductor group 42, becomes greater than zero, the first jig 81 and the second jigs 82 are removed.

[0017] Thereafter, the first conductor group 41 and the second conductor group 42 are further moved and connected to each other outside the slot 3 as shown in the lower part of Fig. 2. The connection between the first conductor group 41 and the second conductor group 42 will be described in detail as follows. That is, the leg end portion 402E of the first conductor group 41 is connected to the inclined end portion 401E of the second conductor group 42. Furthermore, the leg end portion 402E of the second conductor group 42 is connected to the inclined end portion 401E of the first conductor group 41.

[0018] Fig. 3 is a diagram showing the L-shaped coils 400 in the slots 3. Fig. 3 shows only four of the many slots 3 provided in the stator core 2. In Fig. 3, hatching is used to distinguish between the first conductor group 41 and the second conductor group 42. In this embodiment, two L-shaped coils 400 are inserted into one slot 3, and one L-shaped coil 400 from the first conductor group 41 and one L-shaped coil 400 from the second conductor group 42 are inserted into each slot 3.

[0019] As described above, the first conductor group 41 is inserted from the negative side toward the positive side of the Z axis, and the second conductor group 42 is inserted from the positive side toward the negative side of the Z axis. Therefore, each L-shaped coil 400 advances in the radial direction of the slot 3 without other L-shaped coils 400 present until it reaches halfway in the thickness direction of the stator core 2, and then advances using the other L-shaped coils 400 as guides after it reaches halfway in the thickness direction. Therefore, even after the first jig 81 and the second jigs 82 are removed in the second state shown in the middle of Figure 2, the adjacent other L-shaped coils 400 continue to serve as guides, improving the positional accuracy of the coils.

[0020] FIG. 4 is a diagram showing a first state. The upper part of FIG. 4 shows a perspective view of the stator 1, and the lower part of FIG. 4 shows a front view of the first jig 81. FIG. 4 shows the stator 1 viewed from the same perspective as FIG. 1, with the first conductor group 41 and the second conductor group 42 arranged on either side of the stator core 2. The first jig 81 is arranged to surround the outside of the first conductor group 41 near the end on the negative side of the Z axis. The second jig 82 is arranged to surround the outside of the second conductor group 42 near the end on the positive side of the Z axis. Since the first jig 81 and the second jigs 82 have the same configuration, the configuration of the first jig 81 will be described below as a representative.

[0021] The first jig 81 has holding holes 810 for holding the first conductor group 41. Similar to the L-shaped coil 400 that constitutes the first conductor group 41, the holding holes 810 have two rows, an inner row and an outer row. The first conductor group 41 is a collection of holding elements 81E. The first jig 81 is held by a jig holder (not shown).

[0022] FIG. 5 is a diagram showing the holding element 81E. FIG. 5 shows front and top views of the holding element 81E, and further shows the holding state and the released state. The first conductor group 41 shown at the bottom of FIG. 4 is a front view of the holding state. The holding element 81E forms a holding hole 810 together with other adjacent holding elements 81E. The holding element 81E can be switched between the holding state and the released state by rotating the rotating portion 81ER. In the released state, the position of the holding element 81E changes, so that the holding hole 810 is no longer formed, and the L-shaped coil 400 is released.

[0023] Fig. 6 is a diagram showing the second state. The upper part of Fig. 6 shows a perspective view of the stator 1, and the lower part of Fig. 6 shows a front view of the first jig 81. Fig. 6 corresponds to Fig. 4. In Fig. 6, the first conductor group 41 and the second conductor group 42 overlap in the XY plane. Furthermore, in the second state, the first jig 81 and the second jig 82 do not hold the first conductor group 41 and the second conductor group 42, respectively. As shown in the lower part of Fig. 6, the holding element 81E of the first jig 81 is in a released state.

[0024] FIG. 7 illustrates a first comparative example manufacturing method for the stator 1. Comparing FIG. 7 with FIG. 2, the orientation of the stator 1 is rotated 90 degrees, but the direction of gravity remains unchanged from the bottom side of the figure. In the first comparative example manufacturing method, the first conductor group 41 and the second conductor group 42 are moved along the Z axis, which is parallel to gravity. The first conductor group 41 moves in the direction of gravity, and the first jig 81 holds the upper part, so adjusting the position of the leg end 402E is not particularly difficult. However, the second conductor group 42 is held by the second jig 82 on the lower side in the Z axis direction, and is moved vertically upward, which reduces the positional accuracy of the leg end 402E. Therefore, the manufacturing method of the present embodiment shown in FIG. 2 is superior in terms of accuracy to the first comparative example manufacturing method.

[0025] FIG. 8 illustrates a second comparative example manufacturing method for the stator 1. In the second comparative example manufacturing method, the orientation of the stator core 2 is changed so that the L-shaped coil 400 is inserted into the stator core 2 in the direction of gravity. Specifically, the first conductor group 41 is inserted in the same manner as in the first comparative example manufacturing method. However, once the insertion of the first conductor group 41 is complete, the stator core 2 is rotated half a turn around the Y axis together with the inserted first conductor group 41. This allows not only the first conductor group 41 but also the second conductor group 42 to be inserted into the stator core 2 in the direction of gravity. However, misalignment is unavoidable when rotating the stator core 2 around the Y axis. Another problem is the need for a mechanism for rotating the stator core 2 around the Y axis and space for rotating the stator core 2. Therefore, the manufacturing method of this embodiment shown in FIG. 2 is superior to the second comparative example manufacturing method in terms of accuracy, the amount of equipment required, and the footprint.

[0026] The above-described embodiment provides the following advantageous effects. (1) The stator 1 includes an annular stator core 2 having an imaginary axis as its axis, a plurality of slots 3 provided in the stator core 2, and an L-shaped coil 400 arranged next to each of the slots 3. The manufacturing method of the stator 1 includes a step of inserting the L-shaped coil 400 into the slot 3 of the stator core 2 whose imaginary axis is substantially horizontal. This allows for easy manufacturing of a highly accurate stator 1. For example, as in the first and second comparative manufacturing methods, it is also possible to insert the L-shaped coil 400 into a stator core 2 whose imaginary axis is vertical. However, both the first and second comparative manufacturing methods are inferior in accuracy to the method of this embodiment.

[0027] (2) The L-shaped coil 400 includes legs 402 and inclined portions 401 inclined relative to the legs 402. The manufacturing method of the stator 1 includes a first state shown in FIG. 2 in which a first conductor group, which is a plurality of conductors, is annularly arranged by a first jig with one side inclined and the legs approximately horizontal, and a second conductor group, which is a plurality of conductors, is annularly arranged by a second jig with the other side inclined and the legs approximately horizontal. In the first state, the legs 402 of the first conductor group 41 are inserted into the slots 3 from the negative side to the positive side of the Z axis. Furthermore, the legs 402 of the second conductor group 42 are inserted into the slots 3 from the positive side to the negative side of the Z axis. Therefore, the stator 1 can be manufactured using the L-shaped coil 400, thereby achieving reduced manufacturing costs and improved accuracy.

[0028] (3) With the legs 402 of the first conductor group 41 and the legs 402 of the second conductor group 42 overlapping in the Z-axis direction, the first jig 81 and the second jig 82 are removed from the conductors, the first conductor group 41 is further inserted toward the other side, and the second conductor group 42 is further inserted toward one side. Therefore, even after the first jig 81 and the second jig 82 are removed, the other adjacent L-shaped coils 400 serve as guides, improving the positional accuracy of the coils.

[0029] (4) Each leg end 402E of the first conductor group 41 is coupled to each inclined end 401E of the second conductor group 42, and each inclined end 401E of the first conductor group 41 is coupled to each leg end 402E of the second conductor group 42.

[0030] (Variation 1) In the above-described embodiment, two L-shaped coils 400 are inserted into each slot 3, but one or three or more L-shaped coils 400 may be inserted into a slot 3. When three or more L-shaped coils 400 are inserted into a slot 3, the L-shaped coils 400 belonging to the first conductor group 41 and the L-shaped coils 400 belonging to the second conductor group 42 may be arranged alternately in the radial direction.

[0031] Fig. 9 is a diagram showing a slot 3 in Modification 1. In the example shown in Fig. 9, three L-shaped coils 400 are inserted into one slot 3. In this way, even if the number of L-shaped coils 400 inserted into one slot changes, insertion can be performed smoothly after removing the jigs, as shown in Fig. 2. Specifically, when the first jig 81 and the second jigs 82 are removed from the conductors with the leg portions 402 of the first conductor group 41 and the leg portions 402 of the second conductor group 42 overlapping in the Z-axis direction, the tip of the L-shaped coil 400 can move inside the slot 3 using the other L-shaped coils 400 as a guide.

[0032] The present invention is not limited to the contents of the embodiments and modifications, and other embodiments that are conceivable within the scope of the technical idea of ​​the present invention are also included within the scope of the present invention.

[0033] 1: Stator 2: Stator core 3: Slot 4: Stator conductor 41: First conductor group 42: Second conductor group 81: First jig 81E: Holding element 81ER: Rotating portion 82: Second jig 400: L-shaped coil (conductor) 401: Inclined portion 401E: Inclined end portion 402: Leg portion 402E: Leg end portion 810: Holding hole

Claims

1. A method for manufacturing a stator comprising: an annular stator core having an imaginary axis as its axis; a plurality of slots provided in the stator core; and conductors arranged in line with each of the slots, wherein the conductors are inserted into the slots of the stator core, with the imaginary axis being approximately horizontal.

2. A manufacturing method for a stator as described in claim 1, wherein the conductor has legs and inclined portions inclined relative to the legs, a first conductor group consisting of a plurality of the conductors is arranged in a ring shape on a first jig with one side being the inclined portion and the legs being approximately horizontal, and a second conductor group consisting of a plurality of the conductors is arranged in a ring shape on a second jig with the other side being the inclined portion and the legs being approximately horizontal, and the legs of the first conductor group are inserted into the slots from the one side, and the legs of the second conductor group are inserted into the slots from the other side.

3. A method for manufacturing a stator as described in claim 2, wherein the conductors included in the first conductor group and the conductors included in the second conductor group are inserted into each of the slots, and while the legs of the first conductor group and the legs of the second conductor group are overlapping in the direction of the imaginary axis, the first jig and the second jig are removed from the conductors, the first conductor group is further inserted toward the other side, and the second conductor group is further inserted toward the one side.

4. A method for manufacturing a stator as described in claim 2, comprising: joining an end of each of the legs of the first conductor group to an end of each of the inclined portions of the second conductor group; and joining an end of each of the inclined portions of the first conductor group to an end of each of the legs of the second conductor group.