JP6764797B2 - Linear motor and cooling method for linear motor - Google Patents

Description

The present invention relates to a linear motor and a method for cooling the linear motor.

A linear motor is a motor that emits power in a linear direction, and is used in many fields because it can obtain linear power with a relatively small structure.

The thrust generation mechanism in a linear motor is composed of a stator and a mover. The mover is configured by arranging permanent magnets in a row so that the magnetic poles are alternately inverted along the traveling direction. In addition, the stator consists of a plurality of magnetic poles arranged so as to sandwich the permanent magnet of the mover, a core that continuously connects these magnetic pole teeth, and a winding wound around the plurality of cores. There is. Such a technique is described in, for example, Japanese Patent Application Laid-Open No. 2013-102695 (Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-102695

In a linear motor, a stator is excited by applying an electric current to the winding of the linear motor, and a thrust is generated in the mover by an electromagnetic force, and heat caused by the electric current is generated in the winding. Here, in general, in order to obtain the structural strength of the linear motor, a structure in which the stator is reinforced with inclusions or the stator is surrounded by a metal case or the like is applied, and therefore for cooling. There is no gap for spraying a fluid such as air on the winding inside the stator, and there is a problem that cooling is difficult.

As a countermeasure, a structure having a cooling port or a structure in which a passage of a cooling medium is embedded is proposed, but the structure becomes complicated and the entire device becomes large.

In addition, in general, windings that are insulated from each other with an insulator film or resin are used, and since the magnetic material that constitutes the magnetic pole teeth has low thermal conductivity, it extends from the winding to the motor external space. There is a problem that the thermal resistance of the heat transfer path increases and it is difficult for the winding to dissipate heat. Further, there is a problem that the insulator deteriorates when the heat dissipation is small and the winding becomes high temperature. Therefore, the present invention reduces the temperature of the winding by increasing the thermal conductivity from the winding to the external space. It is an object of the present invention to provide a linear motor having increased output and thrust, and a cooling method for the linear motor.

In order to solve the above problems, for example, the configuration described in the claims is adopted.

The linear motor according to the present invention includes a magnet row unit composed of permanent magnets in which poles are alternately arranged in series and an armature unit, and the armature unit includes a plurality of armatures and the armature. The armature is composed of spacers sandwiched between the armatures, and the armature includes first magnetic pole teeth and second magnetic pole teeth formed so as to face each other along both sides of the permanent magnet, and the first magnetic pole teeth and the second magnetic pole teeth. a core connecting the pole teeth, a linear motor composed of the first magnetic pole teeth and the armature winding installed in each of the second magnetic pole teeth, said first magnetic pole teeth from the side of the core A heat sink is provided so as to project toward each of the second magnetic pole teeth and is composed of the first magnetic pole tooth and a material having a higher thermal conductivity than the second magnetic pole tooth, and the spacer is the iron core. And in contact with the heat sink, it is composed of a material having a higher thermal conductivity than the iron core, and heat generated in the armature winding is radiated from the heat sink to the outside through the spacer.

The method for cooling a linear motor according to the present invention includes a magnet row unit composed of permanent magnets in which poles are alternately arranged in series and an armature unit, and the armature unit includes a plurality of armatures and the armature. The armature is composed of a spacer sandwiched between armatures, and the armature includes a first magnetic pole tooth and a second magnetic pole tooth formed so as to face each other along both sides of the permanent magnet, and the first magnetic pole tooth and the armature. A method for cooling a linear motor, which comprises an iron core connecting the second magnetic pole teeth and armature windings wound around the first magnetic pole teeth and the second magnetic pole teeth, respectively. It is provided so as to project from the side surface of the iron core toward the first magnetic pole tooth and the second magnetic pole tooth, respectively, and is composed of a material having a higher thermal conductivity than the first magnetic pole tooth and the second magnetic pole tooth. The spacer is in contact with the iron core and the heat sink, is composed of a material having a higher thermal conductivity than the iron core, and heat generated in the armature winding is transferred from the heat sink to the spacer via the spacer. Dissipate heat to the outside.

According to the present invention, it is possible to provide a linear motor in which the temperature rise of the winding due to the energization of an electric current is reduced and the rated output and the rated thrust at the time of natural cooling are increased.

It is a perspective view which shows Example 1 of the linear motor of this invention. It is sectional drawing of FIG. It is another sectional view of FIG. It is explanatory drawing of the magnetic flux path in Example 1. FIG. It is explanatory drawing of the heat flux path in Example 1. FIG. It is a perspective view which shows Example 2 of the linear motor of this invention. It is sectional drawing of FIG. It is a perspective view which shows Example 3 of the linear motor of this invention. FIG. 8 is a cross-sectional view of FIG. It is sectional drawing which shows Example 4 of the linear motor of this invention.

Hereinafter, the configuration of the linear motor of the present invention will be described based on the illustrated examples. In each embodiment, the same reference numerals are used for the same components.

1 to 5 show Example 1 of the linear motor of the present invention.

FIG. 1 is a perspective view of a linear motor 100 according to an embodiment of the present invention. 2 is a sectional view taken along line II in FIG. 1, and FIG. 3 is a sectional view taken along line II-II in FIG. This embodiment is an example in which a three-phase motor is configured, and the armature unit 200 and the magnet row unit 210 in which at least two or more permanent magnets 10 are arranged side by side relatively linearly move. It is a linear motor. One or both of the armature unit 200 and the magnet row unit 210 are fixed to the other structure. Generally, the magnet row unit 210 is used as the movable side, but this embodiment is not limited to this. The magnet row unit 210 is configured by connecting permanent magnets 10-1, 10-2 ... Permanent magnets 10-n in parallel. Permanent magnets 10-1, 10-2 ... Are collectively referred to as permanent magnets 10.

The drive direction of the magnet row unit 210 of the linear motor 100 is the front-rear direction. A three-phase linear motor can be configured by arranging the three armatures 102 so that their phases are electrically shifted by 120 °. Similarly, with m armatures, an m-phase drive linear motor can be configured by shifting the phase by 360 ° / m.

The armature unit 200 is configured to sandwich the armatures 102-1, 102-2, 102-3 between the spacers 30-1, 30-2, 30-3, and 30-4, respectively. Here, the spacers 30-1, 30-2, 30-3, and 30-4 are collectively referred to as a spacer 30, and the armatures 102-1, 102-2, and 102-3 are collectively referred to as an armature 102.

In FIG. 2, the magnet row unit 210 is configured by connecting permanent magnets 10-1, 10-2, 10-3, 10-4, 10-5, 10-6, and so on in parallel. In the figure, the permanent magnets 10-1 ... 10-6 are described in isolation, but the permanent magnets 10-1 ... 10-6 are fixedly connected to each other and move integrally.

Arrows 15-1 and 15-2 exemplify the magnetization directions of the permanent magnets 10-1 and 10-2 (the same applies to the permanent magnets 10-3, 10-4, 10-5, 10-6 ...). Has been). In this way, the surface of the permanent magnet 10 facing the magnetic pole teeth is in the magnetization direction. For example, the permanent magnet magnetized in parallel in the vertical direction or magnetized so that the magnetic force has a gradient in the front-back and left-right directions. Permanent magnets are used. The permanent magnet row unit 210 is configured by arranging a plurality of permanent magnets in the driving direction at intervals of magnet pitch P. The permanent magnet rows 210 are arranged so that the magnetization directions of the adjacent permanent magnets 10 are alternated.

1 to 3, as shown in FIG. 3, the armature 102 has a first magnetic pole tooth 114, a second magnetic pole tooth 116, a first magnetic pole tooth 114, and a first magnetic pole tooth 114 facing each other with a gap 122 in between. Windings 104-1 and 104-2 (armature windings 104-1 and 104-) arranged on the iron core 110 connecting the two magnetic pole teeth 116, the first magnetic pole tooth 114, and the second magnetic pole tooth 116, respectively. 2 is generically referred to as an armature winding 104). The first magnetic pole tooth 114, the second magnetic pole tooth 116, and the iron core 110 are formed by laminating a plate-shaped magnetic material (for example, silicon steel or the like) in the front-rear direction. The armature 102 has an opening 42 which is a space having a length H2 in the vertical direction. The depth H2 is formed by the opening 42 penetrating the iron core 110 and cutting a part of the first magnetic pole tooth 116 or the second magnetic pole tooth 114 to the vicinity of the magnet row unit 210, and is formed outside the armature 102. There is a relationship of H2 ≦ H1 with respect to the vertical length H1 between the surface and the bottom surface of the first magnetic pole tooth 116 or the second magnetic pole tooth 114. In the armature winding 104, a conductor (for example, copper or the like) is wrapped with an insulator film or resin.

The armature unit 200 includes three armatures 102-1, 102-2, 102-3 arranged side by side at intervals of armature pitch Q in the drive direction, and armatures 102-1, 102-2 arranged side by side. Spacers 30-2 and 30-3 arranged one or more between 102-3 and one or more spacers 30-2 arranged outside the armatures 102-1, 102-2 and 102-3 arranged side by side, respectively. It is composed of 1 and 30-4. The spacer 30 is made of a substance having a higher thermal conductivity than iron (for example, aluminum, copper, etc.). Although one spacer is arranged above and one below in this embodiment, the shape and number of spacers are not limited to this. The relationship between the armature pitch Q and the magnet pitch P is generally P = 3Q / 2, but this embodiment is not limited to this.

A heat sink 40 is arranged inside the opening 42. The heat sink 40 is in contact with the armature core 110, the spacer 30, the first magnetic pole tooth 114 or the second magnetic pole tooth 116, and may be in contact with an insulator around the armature winding 104. The heat sink 40 is made of the same material as the spacer 30 or a material having a higher thermal conductivity, and if it is the same material as the spacer 30, it may have a structure integrated with the spacer. As described above, the heat sink 40 uses a substance having a sufficiently higher thermal conductivity than the first magnetic pole teeth 114 or the second magnetic pole teeth 116.

FIG. 4 shows the path 110 of the magnetic flux of the iron core of the armature 102. The magnetic flux path 110 is
Closed so as to surround the armature windings 104-1 and 104-2, passing through the first magnetic pole tooth 114, the second magnetic pole tooth 116, passing through the iron core 110, and returning to the first magnetic pole tooth 114 again. Form a path. Since the magnetic flux path of the armature 102 is independent of the magnetic flux path of the other armature, there is no magnetic interference. Therefore, the increase in mutual inductance and the increase in cogging force due to the leakage flux from other phases are small.

FIG. 5 shows the main heat flow velocity paths when the heat generated when the armature winding is energized is the source. In this figure, only one armature 102 (102-1) and spacers 30 (30-1, 30-2) at both ends are shown as an example for explanation, and the internal structure is shown by a broken line. The heat generated in the armature winding 104 collects from the outside to the inside of the first magnetic pole tooth 114 or the second magnetic pole tooth 116 and is transmitted to the iron core portion near the heat sink 40 or the heat sink 40, and the heat sink 40 having a small thermal resistance It is conducted in the vertical direction through it. Then, heat is released from the heat sink 40 to the outside through the spacer 30.

At this time, when the thermal conductivity of the constituent material of the spacer 30 is equal to or higher than that of the heat sink 40, the heat flux is efficiently dissipated from the heat sink 40 to the external space via the spacer 30.

By adopting such a configuration of this embodiment, the thermal resistance of the heat transfer path from the armature winding 104 to the outside of the armature 200 which is the heat dissipation end is reduced, and the heat dissipation efficiency at the center of the coil is improved. , The coil temperature is reduced. By reducing the coil temperature, a larger current can be passed through the winding and the maximum output of the linear motor can be increased. Further, since the temperature of the insulator around the armature winding is lowered, there is an effect of preventing deterioration of the insulator due to heat and extending the service life of the linear motor. Further, when the heat sink 40 and the spacer 30 are configured as an integral structure on an arbitrary contact surface, it is possible to further enhance the cooling effect of the armature winding by eliminating the thermal resistance of the contact portion.

Here, the operation of the linear motor 100 will be described. The three-phase coils of the armatures 102-1, 102-2, and 102-3 are arranged at positions shifted by 120 degrees from each other. A three-phase alternating current is passed through here. The three-phase alternating current is an alternating current whose time phase is 120 degrees out of phase with each other. The positions of the three-phase coils of the armatures 102-1, 102-2, and 102-3 are out of phase with the three-phase AC current that flows by 120 degrees. As a result, the three-phase current that flows through the coil is created. The overlapping magnetic fields of the two generate two magnetic poles that are constantly moving. This is a phenomenon generally called a rotating magnetic field, and in linear it is called a moving magnetic field. Since the magnetic flux density distribution of the moving magnetic field has peaks of the north and south poles at positions shifted by 180 degrees, the moving magnetic field and the north and south poles of the permanent magnet 10 of the magnet train unit 210 are magnetically mutual. The linear motor 100 is driven by the action (suction / repulsion).

6 to 7 show Example 2 of the linear motor of the present invention. The linear motor 300 of the present embodiment shown in the figure is the same as that of the first embodiment except that the configuration thereof is particularly mentioned.

In this embodiment shown in the figure, the configuration is substantially the same as that of the linear motor shown in the first embodiment, but the opening 42 of the linear motor shown in FIG. 2 is closed, and the window portion 52 is formed in the space inside the iron core. It is provided. A heat sink 40 is fitted in the window portion 52. The vertical length H3 of the window portion has a relationship of H3 <H1 with respect to the vertical length H1 between the outer surface of the armature 102 and the bottom surface of the magnetic pole teeth 116 or 114.

According to this embodiment, not only the same effect as that of the first embodiment can be obtained, but also the rigidity of the armature 102 is increased, and the amount of deformation with respect to an external force from the left-right direction is particularly small.

8 to 9 show Example 3 of the linear motor of the present invention. The linear motor 400 of the present embodiment shown in the figure is the same as that of the first embodiment except that the configuration thereof is particularly mentioned.

In this embodiment shown in the figure, the configuration is substantially the same as that of the linear motor shown in the first embodiment, but a heat sink 60 is provided between the iron core 110 and the armature winding 104, and the armature 102 is a heat sink. One or more 60s are arranged. The heat sink 60 is in contact with the armature core 110 and the spacer 30. Further, the heat sink 60 is close to the insulator around the armature winding 104, and if a gap is generated between the heat sink 60 and the insulator, the gap is made of a thin metal plate (for example, aluminum or copper). It may be filled. The heat sink 60 is made of the same material as the spacer 30 or a material having a higher thermal conductivity, and when it is the same material as the spacer 30, it may have a structure integrated with the spacer.

According to this embodiment, not only the same effect as that of the first embodiment can be obtained, but also the spacer 60 serves as a heat transfer member of the armature winding 104 which is a heat source and reaches the outside of the armature which is a heat radiation end. Since the heat transfer path is increased, the heat resistance from the armature winding 104 to the outside of the armature is reduced, the amount of heat radiated from the spacer 30 is increased, and the effect of reducing the temperature of the armature winding can be obtained.

The same effect can be obtained even in a structure in which the heat sink 40 is fitted in the window portion instead of the opening portion as in the second embodiment.

FIG. 10 shows Example 4 of the linear motor of the present invention. The linear motor 500 of the present embodiment shown in the figure is the same as that of the third embodiment except that the configuration thereof is particularly mentioned.

In the present embodiment shown in the figure, the configuration is substantially the same as that of the linear motor shown in the third embodiment, but the protrusion 65 is provided at the end of the heat sink 62. The protrusion of the heat sink 62 may be close to and in contact with the corner of the armature winding 104.

According to this embodiment, not only the same effect as that of the third embodiment can be obtained, but also the protrusion of the heat sink 62 can prevent the armature winding from coming off from the magnetic pole teeth.

10 Permanent magnet 15 Magnetization direction 40, 60, 62 Heat sink 42 Opening 52 Window 65 Projection 100, 300, 400, 500 Linear motor 102 Armature 104 Armature winding 110 Iron core 114 First magnetic pole tooth 116 Second Magnetic pole tooth 122 Air gap 200 Armature unit 210 Magnet row unit

Claims (8)

It has a magnet row unit composed of permanent magnets in which poles are alternately arranged in series, and an armature unit. The armature unit is composed of a plurality of armatures and a spacer sandwiched between the armatures. The armature is composed of a first magnetic pole tooth and a second magnetic pole tooth formed so as to face each other along both surfaces of the permanent magnet, and an iron core connecting the first magnetic pole tooth and the second magnetic pole tooth. a linear motor consists of the first magnetic pole teeth and the armature winding installed in each of the second magnetic pole teeth,
Wherein provided from the side surface of the core so as to protrude toward the each of the second magnetic pole teeth and the first magnetic pole teeth are constituted by the material having high thermal conductivity than the first pole tooth and the second pole tooth Equipped with a heat sink
The spacer is made of a substance that comes into contact with the iron core and the heat sink and has a higher thermal conductivity than the iron core.
A linear motor that dissipates heat generated in the armature winding from the heat sink to the outside via the spacer . The linear motor according to claim 1.
A linear motor in which the heat sink is arranged inside the armature winding. The linear motor according to claim 1 or 2 .
A linear motor in which the heat sink is arranged outside the armature winding. The linear motor according to any one of claims 1 to 3.
A linear motor in which the heat sink is the same substance as the spacer. A linear motor as claimed in any one of claims 1 to 3,
A linear motor in which the heat sink is a different substance from the spacer. The linear motor according to claim 4.
A linear motor in which the heat sink is integrally formed with the spacer on an arbitrary contact surface. The linear motor according to claim 3 .
A linear motor in which the heat sink arranged on the outside of the armature winding prevents the armature winding from coming off. It has a magnet row unit composed of permanent magnets in which poles are alternately arranged in series, and an armature unit. The armature unit is composed of a plurality of armatures and a spacer sandwiched between the armatures. The armature is composed of a first magnetic pole tooth and a second magnetic pole tooth formed so as to face each other along both surfaces of the permanent magnet, and an iron core connecting the first magnetic pole tooth and the second magnetic pole tooth. a the linear motor cooling method consists of first magnetic pole teeth and the armature windings respectively wound around the said second magnetic pole teeth,
The linear motor, which is provided from the side surface of the core so as to protrude toward the each of the second magnetic pole teeth and the first magnetic pole teeth, the thermal conductivity than the second magnetic pole teeth and the first magnetic pole tooth Equipped with a heat sink composed of high material
The spacer is made of a substance that comes into contact with the iron core and the heat sink and has a higher thermal conductivity than the iron core.
A cooling method for a linear motor that dissipates heat generated in the armature winding from the heat sink to the outside via the spacer .

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