JP4476502B2 - Linear motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear motor having a closed magnetic path, and more particularly to a linear motor that enables long-distance conveyance by supporting a permanent magnet over the entire travel stroke range.
[0002]
[Prior art]
Conventionally, for example, Japanese Patent Laid-Open No. 63-310361 discloses a linear pulse motor having a structure in which lead wire processing is simplified and can be manufactured at low cost. The structure of the linear motor is a structure in which a two-phase pulse rotation motor is linearly developed.
[0003]
[Problems to be solved by the invention]
The conventional linear motor has a problem that it cannot provide a linear motor having a closed magnetic path that enables long-distance conveyance by supporting a permanent magnet over the entire travel stroke range.
An object of this invention is to provide the linear motor which has a closed magnetic circuit which enabled the long distance conveyance by supporting a permanent magnet in the whole range of a travel stroke.
[0004]
[Means for Solving the Problems]
The linear motor of the present invention is a linear motor that forms a closed magnetic path by causing a core around which a coil is wound to face the front and back of a permanent magnet. The core is composed of a plurality of core divided bodies, and is opposed to the front side. The plurality of facing portions are opposed to each other, with the front-side facing portion and the back-side facing portion of the facing portion of the adjacent core divided body staggered. The coil is commonly wound around the hook-shaped portion in which the front-side facing portion and the back-side facing portion of the adjacent core divided bodies are extended so that the directions of the magnetic fluxes formed by the magnetic pole teeth of the portions are staggered. And a support member for supporting the permanent magnet between the front-side facing portion and the back-side facing portion constituting the facing portion, wherein the supporting member has a projecting portion along the traveling direction. And
[0005]
In this case, a slit groove through which the protruding portion of the support member is inserted can be formed in the traveling direction between the front-side facing portions of the adjacent facing portions of the core.
[0006]
This linear motor can support the permanent magnet over the entire travel stroke range even in a linear motor having a closed magnetic path with the core facing the front and back of the permanent magnet, thereby forming a long travel path and a long distance. Can be realized.
[0007]
In addition, the core can be formed by alternately turning over a plurality of core divisions having the same shape in the running direction.
[0008]
Thereby, a core can be manufactured simply and at low cost.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a linear motor according to the present invention will be described below with reference to the drawings.
[0009]
1 to 5 show a first embodiment of a linear motor of the present invention.
As shown in FIG. 2, the linear motor of this embodiment forms a closed magnetic circuit by causing a core 1 around which a coil 2 is wound to face an upper surface 3 a and a lower surface 3 b of a permanent magnet 3. A slit groove 5 into which a part of the support member 4 of the permanent magnet 3 is inserted is formed in the traveling direction in the front-side facing portion 11 of the core 1 facing the upper surface 3a of 3.
[0010]
As shown in FIG. 1, the core 1 is formed by alternately stacking a plurality of symmetrical core divided bodies 1a and 1b in the traveling direction with a slight gap between the core divided bodies 1a and 1b. ing. These core division | segmentation bodies 1a and 1b consist of the same shape, and are made into the symmetrical shape by turning over alternately.
As shown in FIGS. 1 to 2, each core divided body 1 a, 1 b is integrally extended from one end of the hook-shaped part 13 around which the coil is wound, and the upper surface of the permanent magnet 3. The front side opposing part 11 which opposes, and the back side opposing part 12 which is integrally extended from the other end of the bowl-shaped part 13, and opposes the lower surface of the permanent magnet 3 are provided.
And in order to form the slit groove | channel 5 with the front side opposing part 11 of adjacent core division body 1a, 1b, the front side opposing part 11 is formed in length a little shorter than the half of the back side opposing part 12. FIG.
With such a configuration of the core 1, it is possible to widen the slit groove 5 by shifting the core divided bodies 1 a, 1 b to the outside, and the permanent magnet 3 can be removed from the widened slit groove 5. And maintenance inspection can be performed easily.
[0011]
Moreover, although the core division bodies 1a and 1b are made into the integral structure in a present Example, in order to improve the workability | operativity at the time of attaching the coil 2, it is also possible to make it a 2 division structure.
Further, the core divided bodies 1a and 1b can be structured such that thin punched steel plates are laminated or can be made into an integrated structure with a single iron core.
And the thickness of the core division | segmentation bodies 1a and 1b is determined by the space | interval of the permanent magnet 3 to be used, and the space | gap with the permanent magnet 3 which opposes leaves the space | interval of the extent which the permanent magnet 3 and the supporting member 4 do not contact. .
[0012]
The reason why the gap is formed when the core divided bodies 1a and 1b are overlapped is to increase the magnetic resistance so that the magnetic flux passing through one core divided body 1a does not enter the adjacent core divided body 1b.
[0013]
On the other hand, the permanent magnet 3 and the support member 4 which enter the core 1 are shown in FIG.
For the permanent magnets 3 arranged so that the magnetic flux passes vertically, the support member 4 includes a back plate 4a fixed to the upper surface of these permanent magnets 3 with an adhesive or the like, and an upper side from the center in the width direction of the back plate 4a. Are formed in a T-shaped cross section by the suspension plate 4b projecting from.
The support member 4 is made of a non-magnetic material such as stainless steel or aluminum, and the suspension plate 4b is appropriately fixed to the fixed member of the equipment through the slit groove 5 of the core 1.
According to the support member 4 and the slit groove 5, even in a linear motor having a closed magnetic path, the permanent magnet 3 can be supported over the entire travel stroke range, thereby forming a long travel path for the linear motor. Long-distance conveyance can be realized, and the permanent magnet 3 can be laid in a simple and stable state.
[0014]
In addition, as shown in FIG. 2, the coil 2 is wound around the bowl-shaped portion 13 of the stacked core divided bodies 1a and 1b.
The laminated core divided bodies 1a and 1b are driven by a single coil 2, and a magnetic flux is generated by the same magnetic field. By reducing the distance between the permanent magnet 3 and the core 1 as long as they do not mechanically contact each other, the efficiency, which is a drawback of the linear motor, can be increased to the same extent as that of a rotary motor.
There is also a gap between the core 1 and the coil 2, and the coil 2 and the core 1 are cooled by flowing air for cooling.
The core 1 around which the coil 2 is wound can be used, for example, to drive a portion that performs a linear motion of a transport device that operates in a semiconductor factory, a liquid crystal panel factory, or the like so as to be fixed to a transport vehicle.
[0015]
FIG. 4 shows a side surface of a linear motor driven by three phases.
A coil 2 is wound around a core 1 in which a plurality of core divided bodies 1a and 1b are laminated, the core 1 is shifted in phase and disposed on the movable side, and driving force is obtained from the permanent magnet 3 on the fixed side.
[0016]
The flow of magnetic flux in the core 1 is shown in FIG.
Since the core 1 is wound so that the coil 2 extends over all the core divided bodies 1a and 1b, the direction of the magnetic flux passing through each core divided body 1a and 1b is the same.
This magnetic flux is passed through the coil 2 by alternately changing the front and back of the adjacent core divided bodies 1a and 1b, so that the magnetic flux passes from the top to the bottom as shown in the figure, and from the bottom to the top. The direction can be reversed when passing through.
By providing a gap between the adjacent core divided bodies 1a and 1b, this magnetic flux is prevented from entering the adjacent core divided bodies 1a and 1b, which contributes to an improvement in the utilization efficiency of the magnetic flux.
[0017]
In addition, the generation of thrust of the linear motor is proportional to the length of the cross section of the magnetic path passing from the core 1 to the permanent magnet 3, so that it is compared with a closed magnetic path having a tunnel structure without the slit groove 5 above and below the permanent magnet 3. Then, in the core 1 of the present embodiment, the generation of thrust at the front facing portion 11 is reduced to about half, but in the linear motor of the present embodiment, the high use efficiency of the magnetic flux of the tunnel structure without the slit groove 5 and The advantages of both the convenience of handling a general-purpose linear motor driven by only one side of the permanent magnet can be exhibited.
[0018]
As described above, in the first embodiment, an example of a linear motor having three coils for three-phase driving has been shown. However, in order to make the linear motor two-phase or reduce driving and thrust ripples, a multi-phase structure is further provided. It can also be.
[0019]
Next, a second embodiment of the linear motor of the present invention will be described with reference to FIGS.
This linear motor constitutes a closed magnetic circuit by making the core 6 face the front and back of the permanent magnets 71 and 72. A pair of permanent magnets 71 and 72 are vertically arranged in parallel. Each of the permanent magnets 71 and 72 is made to face the core 6, and an opening 8 through which the permanent magnets 71 and 72 are inserted is continuously formed in one end of the facing core 6 in the traveling direction.
[0020]
As shown in FIG. 6, the core 6 is formed by alternately stacking a plurality of symmetrical core divided bodies 6 a and 6 b in the running direction with a slight gap between the core divided bodies 6 a and 6 b. ing. These core division bodies 6a and 6b are of the same shape, and are made symmetrical by turning over alternately.
As shown in FIGS. 6 to 7, the core divided body 6 a is integrally extended from one end of the hook-shaped portion 63 around which the coil 2 is wound and the outer surface 71 a of the permanent magnet 71. A front-side facing portion 61 and a back-side facing portion 62 that extends integrally from the other end of the flange-shaped portion 63 and faces the inner surface 71 b of the permanent magnet 71.
Similarly, as shown in FIGS. 6 to 7, the core divided body 6 b is integrally extended from one end of the hook-shaped portion 63 around which the coil 2 is wound, and the outer surface of the permanent magnet 72. A front-side facing portion 61 that faces 72 a and a back-side facing portion 62 that extends integrally from the other end of the bowl-shaped portion 63 and faces the inner surface 72 b of the permanent magnet 72 are provided.
[0021]
On the other hand, the permanent magnet is a pair of permanent magnets 71 and 72 arranged side by side, a connecting member 73 that connects these permanent magnets 71 and 72, and a support that supports the permanent magnets 71 and 72 via the connecting member 73. And a member 74. In addition, as shown in FIG. 8, each permanent magnet 71 and 72 has many magnets with different polarities arranged alternately in the running direction with a slight gap.
And each core division body 6a, 6b has adjacent core division body 6a, 6b so that the position of the opening 8 of each permanent magnet 71, 72 and the core division body 6a, 6b which were arranged in parallel may correspond. The polymerization is performed by shifting the width of the opening 8.
Thereby, the core 6 can be formed by alternately turning the core divided bodies 6a and 6b formed in the same shape upside down, and the core 6 can be manufactured easily and at low cost.
[0022]
Further, as shown in FIG. 7, the coil 2 is wound around the flange-shaped portion 63 of the core divided bodies 6a and 6b that are stacked in plural.
The laminated core divided bodies 6a and 6b are driven by a single coil 2, and a magnetic flux is generated by the same magnetic field. By reducing the distance between the permanent magnets 71 and 72 and the core 6 within a range where they do not mechanically contact each other, the efficiency, which is a drawback of the linear motor, can be increased to the same extent as that of a rotary motor.
There is also a gap between the core 6 and the coil 2, and the coil 2 and the core 1 are cooled by flowing air for cooling.
The core 6 around which the coil 2 is wound can be used, for example, to drive a portion that performs a linear motion of a transfer device that operates in a semiconductor factory, a liquid crystal panel factory, or the like, so as to be fixed to a transfer vehicle.
[0023]
Thus, in the linear motor of the second embodiment, the opening 6 through which the permanent magnets 71 and 72 are inserted is formed in the traveling direction at one end of the core 6 facing the front and back of the permanent magnets 71 and 72. Even in a linear motor having a closed magnetic path opposed to the front and back surfaces of the permanent magnets 71 and 72, the permanent magnets 71 and 72 can be supported over the entire travel stroke range. Since the conveyance is realized and the permanent magnets 71 and 72 can be removed from the opening 8 and removed, the linear motor can be easily disassembled and maintained.
Further, by arranging a pair of permanent magnets 71 and 72 side by side and making the core 6 face each of the permanent magnets 71 and 72 arranged side by side, the magnetic flux is increased up to about twice that of the first embodiment. By increasing the cross-sectional area, the driving force of the motor can be increased up to about twice.
[0024]
【The invention's effect】
According to the linear motor of the present invention, even in a linear motor having a closed magnetic path in which the core faces the front and back of the permanent magnet, the permanent magnet can be supported over the entire travel stroke range, thereby forming a long travel path. Thus, long-distance conveyance can be realized.
[0025]
In addition, the core can be manufactured easily and at low cost by forming the core by alternately turning over a plurality of core segments having the same shape and alternately stacking them in the running direction.
The cores can be formed by alternately turning over and stacking the cores, whereby the cores can be manufactured easily and at low cost.
[Brief description of the drawings]
FIG. 1 shows a first embodiment of a linear motor of the present invention, in which (a) is a perspective view of a core and (b) is a perspective view of a core divided body.
FIG. 2 is a cross-sectional front view showing the linear motor of the embodiment.
FIG. 3 is a partial perspective view showing a permanent magnet and a support member of the same embodiment.
FIG. 4 is a side view showing the linear motor of the embodiment.
FIG. 5 is a perspective view showing the flow of magnetic flux in the core divided body.
6A and 6B show a second embodiment of the linear motor of the present invention, in which FIG. 6A is a perspective view of a core, and FIG. 6B is a perspective view of a core divided body.
FIG. 7 is a sectional front view showing the linear motor of the embodiment.
FIG. 8 is a partial perspective view showing the permanent magnet of the same example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Core 1a Core division body 1b Core division body 11 Front side opposing part 12 Back side opposing part 13 Cage-shaped part 2 Coil 3 Permanent magnet 3a Permanent magnet upper surface 3b Permanent magnet lower surface 4 Support member 4a Back plate 4b Suspension plate 5 Slit groove 6 Core 6a Core division body 6b Core division body 61 Front side facing portion 62 Back side facing portion 63 Gutter-shaped portion 71 Permanent magnet 71a Permanent magnet outer surface 71b Permanent magnet inner surface 72 Permanent magnet 72a Permanent magnet outer surface 72b Permanent magnet inner surface 73 Connecting member 74 Support member 8 Opening

Claims (3)

In a linear motor that forms a closed magnetic path by making a core around which a coil is wound face the front and back of a permanent magnet, the core is composed of a plurality of core divided bodies, and the front facing part and the back facing part are There are a plurality of facing portions, and the facing portions of the facing portions of the adjacent core divided bodies alternate with each other so that the front-side facing portion and the back-side facing portion are staggered to form magnetic pole teeth of the adjacent facing portions. The coil is wound in common on the hook-shaped portion in which the front-side facing portion and the back-side facing portion of the adjacent core divided bodies are extended so that the directions of the magnetic fluxes are staggered, and the facing portion A linear motor comprising a support member for supporting a permanent magnet between a front-side facing portion and a back-side facing portion constituting the linear motor, wherein the support member has a projecting portion along the traveling direction.   2. The linear motor according to claim 1, wherein a slit groove through which the projecting portion of the support member is inserted is formed in a traveling direction between front-side opposing portions of adjacent opposing portions of the core.   3. The linear motor according to claim 1, wherein the core is formed by alternately turning a plurality of core divided bodies having the same shape and alternately overlapping in a running direction.

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