KR101053921B1 - Coil stack and slotless motor having same - Google Patents

Abstract

The coil part laminated body of this invention consists of a pair of extension side and a pair of end side which connect the said extension side, The coil part which wound the coil in the shape of the closed figure which has an opening part in the center in the circumference | surroundings of a motor It is characterized in that the laminated by spaced apart a certain distance along the direction.

Description

COIL STRUCTURE AND SLOTLESS MOTOR INCLUDING THE SAME}

The present invention relates to a coil unit stack and a slotless motor having the same, and to a slotless motor having no slot formed in a core in which a coil is wound in a conventional motor, and a coil unit stack adopted in such a slotless motor. will be.

In general, a small motor used for servo control of an articulated robot or a multimedia device includes a permanent magnet in which N poles and S poles are alternately magnetized, and a coil wound core. One of the permanent magnets or cores is a stator and the other is a rotor.

The motor having such a configuration obtains the action force in the rotational direction by the attraction force and the repulsive force between the changing magnetic field formed by switching the current in the coil and the magnetic field of the magnetized permanent magnet to rotate the rotor.

That is, a plurality of slots are formed in the core, and each coil part is formed by winding an insulation coil several times in each slot, and the coil part is appropriately determined according to the number of slots and the number of magnet poles of the permanent magnet. When switching, each slot alternates with one of the N pole and the S pole, and the attraction force and the repulsive force act between the slot and the magnetizing pole, and the force of the attraction force and the repulsive force acts as the rotational force of the rotor to rotate the rotor. .

As such, it is common to form slots in the core and to coil coils in each slot, but the process of winding the coils in slots having a complicated shape to improve the magnetic flux forming efficiency is not easy, and small servo control with small diameter In the case of a motor, a process of forming a plurality of slots in a small space and winding a coil in each slot without an empty space is more difficult, and the space utilization inside the motor is reduced and the strength of magnetic fluxes formed per unit area is reduced. When the desired torque or rotation speed is difficult to implement, there is a problem in that power consumption increases and motor efficiency falls.

The present invention has been made to improve the above-mentioned problems, and to provide a slotless motor that can obtain rotational force only by the coil part without forming a slot in the core.

That is, a plurality of coils wound with an insulating coil are laminated to form a coil part stack, and the coil part stack is inserted between a cylindrical core and a magnet not provided with a slot, and the coil part stack is formed. It is to provide a slotless motor that is rotated by switching a current in each coil part.

Moreover, it is for providing the coil part laminated body of the optimal efficiency employ | adopted for such a slotless motor.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

The coil part laminated body of this invention consists of a pair of extension side and a pair of end side which connect the said extension side, The coil part which wound the coil in the shape of the closed figure which has an opening part in the center in the circumference | surroundings of a motor It is characterized in that the laminated by spaced apart a certain distance along the direction.

Here, the extension side is preferably extended in parallel with the polarization line of the permanent magnet provided inside the motor.

In one embodiment, the coil portion is any one of a quadrangle, a track, and a trapezoidal shape.

In one embodiment, the extension side portion by pressing the extension side of the second coil portion toward the opening portion of the first coil portion with respect to the first coil portion and the second coil portion adjacent to each other among the plurality of coil portions. The lamination thickness of is smaller than the lamination thickness of the end side portion.

In one embodiment, the coil portion has a trapezoidal shape having a longer length of the extended extension side.

On the other hand, the slotless motor of the present invention, the motor shaft to be the center of rotation; A permanent magnet provided on the motor shaft; A core provided in a cylindrical shape around the permanent magnet; A coil part stack sandwiched between the permanent magnet and the core; The coil unit stack includes a pair of extension sides and a pair of end sides connecting the extension sides, and a plurality of coil parts winding the coil in a shape of a closed figure having an opening in the center in a circumferential direction. The stack is spaced apart by a predetermined distance along the, the extension side is characterized in that it extends in parallel with the polarization line of the permanent magnet.

In one embodiment, the core is a plurality of partitions joined together.

The slotless motor according to the present invention has a simple structure and does not form a plurality of slots having a complicated shape in the core, thereby reducing manufacturing costs and improving production efficiency.

In addition, slotless motors have a high density of magnetic fluxes, so the magnetic flux density can be increased, making it easy to secure the desired torque and rotational speed in small motors, and cogging torque, which is one of the causes of pulsation in a slotted motor. (cogging torque) is low, there is an advantage that the vibration and noise due to pulsation is reduced.

In addition, for example, by forming a coil portion laminate by stacking coil portions having a rectangular or trapezoidal shape rather than a rhombic or circular coil portion, the area of the extension side can be increased to increase the magnetic flux linkage density of the permanent magnet, Motor production is possible.

In addition, when stacking coil sections having a rectangular or trapezoidal shape, the thickness of the coil side stack end side becomes thick, so that the core is divided into cores and the core is divided to cope with the difficulty of assembling the coil stack between the core and the permanent magnet. It takes a structure to wrap and assemble some laminates, thereby improving the ease of assembly.

In addition, there is an advantage in that the total thickness of the coil part laminate can be reduced by compressing and stacking the extension side when the coil part is laminated.

On the other hand, when compressing and stacking the extension side of the rectangular coil portion, the coil portion is deformed into a trapezoid, so that the trapezoidal coil portion with an extended extension side compressed to prevent the sawtooth offset is formed on the end portion of the coil portion stack. By laminating to form a coil part laminate, there is an advantage in that the sawtooth offset of the coil part laminate end side can be removed.

A virtual comparative example for contrast with this invention is demonstrated first.

In manufacturing a stator of a slotless motor, an insulated coil is wound into a hexagonal, elliptical, rhombic, or circular shape to form a single coil portion, and a plurality of single coil portions are arranged in a circumferential direction to overlap one single nose. The stator can be manufactured so that some sides are positioned back and forth.

However, as in the present invention, the coil is not provided in a quadrangular, track, or trapezoidal shape so that the extension side extends in parallel with the polarization line of the permanent magnet. In the case of winding the coil part, since the coil extends obliquely from the upper end to the lower end, the magnetic flux that links between the coil middle part is reduced. This can cause a decrease in the back EMF constant (equivalent to the torque constant), which can cause a drop in the motor output.

In the case of applying a rectangular coil as in the present invention to increase the crosslink magnetic flux, the coil part is overlapped with the end edge part according to the coil pitch when a plurality of single coil parts are stacked, and an upper end part of the coil part laminate And because the thickness of the bottom is thick, means for assembling the rotor core is required, the present invention solved this by configuring the core in a plurality of partitions wrapped around the outer side of the coil side laminate.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this process, the size or shape of the components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms that are specifically defined in consideration of the configuration and operation of the present invention may vary depending on the intention or custom of the user or operator. Definitions of these terms should be made based on the contents throughout the specification.

1 is a plan view showing a rectangular coil portion of the present invention. 2 is a side view of FIG. 1. FIG. 3 is a planar development view in which the coil part stack in which the rectangular coil parts shown in FIG. 1 are stacked is unfolded in the circumferential direction of the motor. 4 is a side cross-sectional view taken along the line A-A 'of FIG. FIG. 5 is a planar exploded view showing a sawtooth offset generated when the extension side is pressed against the coil portion laminate shown in FIG. 3.

1 to 5, the first embodiment of the coil part stack 100 of the present invention will be described.

 The coil unit stack 100 according to the present invention is stacked by separating a plurality of coil units 10a by a predetermined distance along the circumferential direction of the motor. The coil part 10a is a winding of an insulating coil in a closed figure shape. The closed figure consists of a pair of extension sides 20 and a pair of end sides 30 connecting the extension sides 20 and has an opening 25 in the center.

In this case, the extension side 20 extends in parallel with the polarization line 232 of the permanent magnet 230. Therefore, it is preferable that the coil part 10a has any shape of a quadrangle as a 1st embodiment, and a trapezoidal shape and a track shape as a 2nd embodiment mentioned later.

Although not shown, the coil portion formed in a track shape has a straight line with an extended edge and a curved end edge with a small amount contributing to the linkage flux, and is substantially equivalent in view of the square and the linkage flux, which are the first embodiment. Do.

Referring to FIG. 4, the laminated structure of the coil part stack is well illustrated. The plurality of coil units 10a are stacked to overlap each other at a predetermined distance along the circumferential direction.

At this time, as a way to reduce the thickness of the coil unit stack 100, by pressing the extension side 20 in the direction of the arrow is pressed to the position indicated by the dotted line. That is, with respect to the first coil part 11 and the second coil part 12 which are adjacent to each other among the plurality of coil parts 10a, the extension side 20a of the second coil part 12 is the first coil part 11. It is pressed toward the opening part 25 of ().

The thickness of the coil part stack 100 in the case of simply stacking the coil parts 10a without undergoing the crimping process is shown by reference numeral T0, and the thickness of the coil part stack 100 in the case of undergoing the crimping process is T1. Has been shown.

However, this thickness reduction is prominent in the extension side 20 portion, the thickness reduction effect can be obtained because there is no empty space by the opening portion 25 at the end side 30 and the coil portion 10a is overlapped as it is. none. This is well illustrated in FIG. 9, where the stack thickness of the end side 30 portion is still T0 since there is little change before and after compression, and the stack thickness T1 of the extended side 20 portion is the stack thickness of the end side 30 portion. It becomes smaller than the thickness T0.

Although the structure of the slotless motor of the present invention will be described later, referring to FIGS. 10 and 11, the coil part stack 100 is disposed around the permanent magnet 230, and then the coil part stack 100 is disposed on the coil part stack 100. Assuming that the cylindrical core 220 made of one part is fitted, the inner diameter of the core 220 fitted to the thickness T1 of the extension side 20 part is caught by the end side 30 part and thus it is not easy to assemble. Can be expected.

As an embodiment for improving this, the present invention has a length shorter in the z-axis direction than the coil part stack 100 so as to be escaped from the end side part 30, and includes a core 220 made up of a plurality of split parts. Take the structure of joining the core 220 parts wrapped around the extension side (20). For example, an embodiment in which two divided cores 220 are bonded at the junction 224 is shown in FIGS. 10 and 11.

Referring back to FIG. 4, when the other side 20a of the extension side 20 is pressed in the direction of the opening 25 shown by the arrow, based on one side 20b of the extension side 20, the extension side that is pressed is pressed. Since one side of the end side 30 approaches the asymmetrical shape by the deformation of the 20a, as shown in FIG. 5, the offset k in the shape of the sawtooth is formed on the end side 30 of the coil part stack 100. Occurs. Since the offset k may be a factor that degrades mechanical or electrical characteristics as well as appearance, it is preferable to provide an offset removing means.

Referring to FIG. 5, since the offset k is a result of reducing the permanent magnet 230 exposed area at the side of the extended side 20a that is pressed, the offset due to the deformation of the extension side 20a to further increase the flux linkage. Means are needed to remove (k). In addition, when the length of the extension side 20a is shortened, the assembly area for assembling the core 220 is reduced or the torque of the motor is reduced when forming the coil part stack 100 to the core 220. Since the constant may vary from the designed value, the second embodiment described below is preferable as a countermeasure.

6 to 8, a second embodiment of the coil part stack 100 of the present invention will be described. 6 is a plan view showing a trapezoidal coil portion 10b of the present invention. FIG. 7 is a planar development view in which the coil part stack 100 in which the trapezoidal coil parts 10b illustrated in FIG. 6 are stacked is unfolded in the circumferential direction of the motor. 8 is a planar exploded view showing a state in which the sawtooth offset is removed when the extension side 20 is pressed against the coil part stack 100 shown in FIG. 7. The side cross-sectional view of the cutting plane C-C 'of FIG. 7 is the same as that of FIG.

In order to reduce the thickness of the coil part stack 100 in the same manner as in the embodiment shown in FIG. 4, the extension side 20 is pressed in the direction of the arrow and pressed to the position indicated by the dotted line. That is, with respect to the first coil part 11 and the second coil part 12 which are adjacent to each other among the plurality of coil parts 10a, the extension side 20a of the second coil part 12 is the first coil part 11. Is pressed toward the opening 25. Even if the pressed side 20a is deformed so that one side of the end side 30 approaches, an asymmetric rectangular winding having a trapezoidal shape is originally arranged, thereby obtaining a coil part stack 100 having a symmetrical shape as shown in FIG. 8.

That is, when the coil part stack 100 is formed on the core 220 by laminating a trapezoidal asymmetric square winding, a coil part stack 100 having a symmetrical shape may be obtained as shown in FIG. 8. When the coil part stack 100 is formed on the core 220 by joining the core 220 divided by the assembled coil part stack 100 therebetween, the coil part stack 100 is symmetrical. As the sawtooth offset does not occur as a reduction in the coupling space of the core 220, which is a rotor can be prevented.

Taking the winding arrangement with coil pitch 3 as an example, it is as follows. End side 30 of both ends are overlapped in a total of four layers and the middle extension side 20 is overlapped in a total of two layers, in order to overlap the two layers by pressing the overlapping extension side 20 arranged in an extension side (20) One side of) should be made longer than the other side 20. That is, considering the thickness of the coil, the length of one side is made long in a trapezoid shape, and at the portion where two sides of the different coils overlap, the long side is compressed in the short side direction, except the end side 30 which is overlapped in four layers. The extension side 20 of the portion is all compressed in two layers to maintain alignment.

FIG. 9 is a side cross-sectional view taken along the cut plane B-B 'of FIG. 5 and cut plane D-D' of FIG. The lamination thickness of the end side 30 part is still T0 since there is little change before and after crimping, and the lamination thickness T1 of the extension side 20 part is smaller than the lamination thickness T0 of the end side 30 part. .

10 is a perspective view showing the internal structure of a motor provided with the coil part stack 100 of the present invention. FIG. 11 is a side sectional view taken along the line E-E 'of FIG. 10; FIG.

The slotless motor of the present invention includes a motor shaft 210 serving as a rotation center, a permanent magnet 230 as a rotor provided on the motor shaft 210, and a stator provided in a cylindrical shape around the permanent magnet 230. As a core 220, the permanent magnet 230 and the coil unit stack 100 that is sandwiched between the core 220 is included. According to the phase angle of the motor shaft 210 measured by the sensor (sensor), the controller (not shown) switches the current in each coil unit.

The divided core 220 is wrapped on both sides of the coil part stack 100 and bonded at the joint part 224 to complete the stator. As a result, the partial coil of the end side 30 overlapped with the free space of the back yoke of the core 220 is positioned, so that the space can be efficiently utilized, and the extension side 20 and the end side 30 substantially face the core 220. ) Does not face the core 220, so the motor efficiency is improved. The inactive part of the yoke, which did not contribute much to the motor constants, is eliminated.

Although embodiments according to the present invention have been described above, these are merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments of the present invention are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the following claims.

1 is a plan view showing a rectangular coil portion of the present invention.

2 is a side view of FIG. 1.

FIG. 3 is a planar development view in which the coil part stack in which the rectangular coil parts shown in FIG. 1 are stacked is unfolded in the circumferential direction of the motor.

4 is a side cross-sectional view taken along the line A-A 'of FIG.

FIG. 5 is a planar exploded view showing a sawtooth offset generated when the extension side is pressed against the coil portion laminate shown in FIG. 3.

6 is a plan view showing a trapezoidal coil portion of the present invention.

FIG. 7 is a planar development view in which the coil part stack in which the trapezoidal coil parts shown in FIG. 6 are stacked is unfolded in the circumferential direction of the motor.

FIG. 8 is a planar exploded view showing a state in which the sawtooth offset is removed when the extension side is pressed against the coil unit laminate shown in FIG. 7.

FIG. 9 is a side cross-sectional view taken along the cut plane B-B 'of FIG. 5 and cut plane D-D' of FIG.

10 is a perspective view showing the internal structure of a motor provided with a coil part laminate of the present invention.

FIG. 11 is a side sectional view taken along the line E-E 'of FIG. 10; FIG.

<Explanation of symbols for the main parts of the drawings>

10a, 10b ... coil part 20 ... extension

25 ... opening 30 ... end side

100 Coil stack 210 Motor shaft

220 ... core 224 ... junction

230 ... permanent magnet 232 ... polarization line

240 ... control unit 250 ... sensor

Claims (8)

A plurality of coil parts wound by a predetermined distance along the circumferential direction of the motor are laminated by a pair of extension sides and a pair of end sides connecting the extension sides, and winding the coils in a closed figure shape having an opening in the center. One, The extension side extends in parallel with the polarization line of the permanent magnet provided in the motor, Pressing the extension side of the second coil portion toward the opening portion of the first coil portion with respect to the first coil portion and the second coil portion adjacent to each other among the plurality of coil portions, the stack thickness of the extension edge portion is increased. It is formed smaller than the laminated thickness of the end side portion, The coil unit stack, characterized in that the length of the extension side is pressed longer trapezoidal shape. delete delete delete A motor shaft to be the center of rotation; A permanent magnet provided on the motor shaft; A core provided in a cylindrical shape around the permanent magnet; A coil part stack sandwiched between the permanent magnet and the core; Including, The coil part stack includes a pair of extension sides and a pair of end sides connecting the extension sides, and a plurality of coil parts winding the coil in a shape of a closed figure having an opening in the center at a constant distance along the circumferential direction. Laminated by spaced apart, The extension side extends in parallel with the polarization line of the permanent magnet, Pressing the extension side of the second coil portion toward the opening portion of the first coil portion with respect to the first coil portion and the second coil portion adjacent to each other among the plurality of coil portions, the stack thickness of the extension edge portion is increased. It is formed smaller than the laminated thickness of the end side portion, And the coil portion has a trapezoidal shape having a longer length of the extended extension side. delete The method of claim 5, The core is a slotless motor, characterized in that a plurality of divided parts bonded to each other. delete

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