Abstract:
Provided are: a linear motor that has increased compactness and that can effectively use magnetic flux; and an apparatus provided with the linear motor. The linear motor has a top mobile element and a bottom mobile element provided below the top mobile element, and an armature has: a top first set of magnetic pole teeth comprising two magnetic pole teeth opposing each other in the vertical direction across a space through which the top mobile element can move in a reciprocating manner; and a bottom first set of magnetic pole teeth comprising two magnetic pole teeth opposing each other in the vertical direction across a space through which the bottom mobile element can move in a reciprocating manner. The linear motor is characterized by the armature being able to be split into an inner component, which has the bottom magnetic pole tooth of the top first set of magnetic pole teeth and the top magnetic pole tooth of the bottom first set of magnetic pole teeth, and a component having approximately the same shape as that of the inner component or outer component and having the bottom magnetic pole tooth of the bottom first set of magnetic pole teeth.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a linear motor and an apparatus using the linear motor. 
       BACKGROUND ART 
       [0002]    PTL 1 and PTL 2 disclose a linear motor which generates thrust to relatively horizontally move between a permanent magnet of a moving element and an armature. 
         [0003]    PTL 1 discloses a configuration in which a magnetic pole includes magnetic pole teeth disposed opposite to each other via a space and a magnetic material connecting the magnetic pole teeth, a plurality of the magnetic poles are included in a moving direction of a moving element, and magnetic fluxes generated by windings disposed to an armature have a same polarity in a plurality of the magnetic poles. 
         [0004]    PTL 2 discloses a linear motor including windings wound around a plurality of magnetic poles (corresponding to a magnetic pole tooth according to the present invention, for example, refer to FIGS. 1 and 12 in PTL 2) and including a plurality of moving elements (FIG. 14). Further, PTL 2 discloses cores which can be divided in an arrangement direction of moving elements and laminated in a moving direction of the moving elements (0047, 0049, FIGS. 7 and 9). Furthermore, PTL 2 discloses that a dimension in a height direction can be reduced in the case where a plurality of moving elements are included (0069, FIG. 17( b )). 
       CITATION LIST 
     Patent Literatures 
       [0005]    PTL 1: JP 2011-223697 A 
         [0006]    PTL 2: WO 2011/154995 A1 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0007]    A configuration of PTL 1 is a linear motor mainly using a magnetic flux in a surface orthogonal to a moving direction of a moving element. When magnetic poles adjacent in the moving direction of the moving element are opposite to each other, leakage of a magnetic flux is caused in the moving direction of the moving element, and a thrust efficiency is reduced. Therefore, in PTL 1, to reduce the leakage, adjacent multiple magnetic poles 3 have a same polarity (0024). In the case where leakage of a magnetic flux is suppressed by the above-described configuration, an interval of magnetic poles having the same polarity is increased, and an apparatus size is increased. 
         [0008]    According to the configuration described in PTL 2, by forming a magnetic pole by laminated cores, for example, an eddy current loss caused by a magnetic flux moving in the X direction in FIG. 9 is reduced. However, in PTL 2, a driving unit in which windings wind around a plurality of magnetic poles, and to effectively use the magnetic flux, the magnetic pole partially has a tapered shape in a part which is not in contact with the windings, and is tapered toward a permanent magnet. Therefore, shapes of laminated plates for forming a laminated core are varied, and types of parts and assemblability need to be improved (refer to FIG. 13). Further, in the case where the laminated core is used, a fixing means is needed to prevent decomposition of the laminated core. However, PTL 2 does not disclose such means. Especially, PTL 2 does not disclose, for example, how each of core parts on an upper side, a middle and a lower side is fixed in the case where the core can be divided in a vertical direction (refer to FIG. 17( b )). In PTL 2, windings are wound around a plurality of magnetic poles. Therefore, an apparatus size is increased as in PTL 1. 
         [0009]    The present is in view of the above-described points, and one of the objects of the present invention is to provide a downsized linear motor which can effectively use a magnetic flux, and an apparatus using the linear motor. 
       Solution to Problem 
       [0010]    To achieve the above object, a linear motor according to the present invention includes an upper moving element which relatively moves in a longitudinal direction with respect to an armature and a lower moving element provided lower than the upper moving element, wherein the armature includes: an upper first magnetic pole tooth pair including two magnetic pole teeth disposed opposite to each other in a vertical direction via a space in which the upper moving element can relatively move; and a lower first magnetic pole tooth pair including two magnetic pole teeth disposed opposite to each other in a vertical direction via a space in which the lower moving element can relatively move, wherein the armature includes: outside parts including an upper magnetic pole tooth of the upper first magnetic pole tooth pair; inside parts including a lower magnetic pole tooth of the upper first magnetic pole tooth pair and an upper magnetic pole tooth of the lower first magnetic pole tooth pair; and a lower magnetic pole tooth of the lower first magnetic pole tooth pair, and the armature can be divided into parts having substantially same shapes with the outside parts or the inside parts. 
       Advantageous Effects of Invention 
       [0011]    According to the present invention, a downsized linear motor which can effectively use a magnetic flux, and an apparatus using the linear motor. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]      FIG. 1  is a perspective view of a linear motor according to a first embodiment. 
           [0013]      FIG. 2  is a perspective view illustrating a cross section on the Y-Z plane in  FIG. 1 . 
           [0014]      FIG. 3  is a perspective cross-sectional view on the X-Z plane in  FIG. 1  on which a permanent magnet is omitted. 
           [0015]      FIG. 4  is a perspective view illustrating a cross section on the plane Y-Z of the linear motor according to the first embodiment indicating a direction of a magnetic flux generated in a space of an upper magnetic pole tooth and a lower magnetic pole tooth. 
           [0016]      FIG. 5  is a perspective cross-sectional view on the Y-Z plane in  FIG. 5 . 
           [0017]      FIG. 6  is a perspective view illustrating a cross section on the Y-Z plane indicating a first magnetic flux path and a second magnetic flux path of the linear motor according to the first embodiment. 
           [0018]      FIG. 7  is a perspective view illustrating an armature for one phase of the linear motor illustrated in  FIG. 5 . 
           [0019]      FIG. 8  is a perspective cross-sectional view on the X-Y plane of the armature for one phase illustrated in  FIG. 7 . 
           [0020]      FIG. 9  is a perspective cross-sectional view on the Y-Z plane of the armature for one phase illustrated in  FIG. 7 . 
           [0021]      FIG. 10  is a view viewing  FIG. 8  from an arrow A direction. 
           [0022]      FIG. 10  is a view viewing  FIG. 9  from an arrow B direction. 
           [0023]      FIG. 12  is a perspective view of a linear motor and illustrates a configuration example of a magnetic path of an armature. 
           [0024]      FIG. 13  is a view illustrating a slit according to a linear motor in a second embodiment. 
           [0025]      FIG. 14  is a perspective view of a linear motor according to the linear motor in the second embodiment. 
           [0026]      FIG. 15  is a top view describing an arrangement example of a cooling pipe of a linear motor according to the linear motor in the second embodiment. 
           [0027]      FIG. 16  is an elevation view of a linear motor according to the linear motor in the second embodiment. 
           [0028]      FIG. 17  is a sectional view cut on a C-C cross-section in  FIG. 15 . 
           [0029]      FIG. 18  is a view illustrating an example of an positional relation of a radial slit. 
           [0030]      FIG. 19  is a side view of an example of a linear motor according to a third embodiment, in which one armature forms U, V, and W phases. 
           [0031]      FIGS. 20( a ) and 20( b )  are YZ sectional views of  FIG. 19  and views describing a second path of a magnetic flux. 
           [0032]      FIG. 21  is a perspective cross-sectional view describing an example of a linear motor forming each of U, V, and W phases by one armature. 
           [0033]      FIG. 22  illustrates an example of a winding phase of the linear motor illustrated in  FIG. 21 . 
           [0034]      FIG. 23  illustrates a configuration example of a linear motor according to a fourth embodiment in which moving elements are formed in two stages. 
           [0035]      FIG. 24  is a cross-sectional schematic view on a YZ plane of the linear motor illustrated in  FIG. 23 . 
           [0036]      FIG. 25  is an elevational sectional view describing a first path of a magnetic flux of the linear motor in which moving elements are formed in two stages. 
           [0037]      FIG. 26( a )  is an elevational sectional view of a linear motor according to a fifth embodiment in which moving elements are formed in four stages.  FIG. 26( b )  is an enlarged view of a projected line connecting portion  45   a  and a recessed line connecting portion  45   b.    FIG. 26( c )  is a perspective view of a linear motor in which three magnetic pole tooth pairs are included in a longitudinal direction, and moving elements are formed in four stages.  FIG. 26( d )  is a side sectional view of  FIG. 26( c ) . 
           [0038]      FIG. 27  is a view illustrating an example of a linear motor in which members forming a magnetic material are laminated in a moving direction of a moving element. 
           [0039]      FIG. 28  is a view illustrating an example of a linear motor in which a magnetic material is integrated with a magnetic pole tooth. 
           [0040]      FIG. 29  is a view illustrating an example off a linear motor in which a magnetic material is disposed on one side with respect to a moving element. 
           [0041]      FIG. 30  is a view illustrating a fixing example of the linear motor illustrated in  FIG. 29 . 
           [0042]      FIG. 31  is a schematic sectional view illustrating an example a positional relation in a refrigerator mounting a hermetic compressor. 
           [0043]      FIG. 32  is a schematic sectional view illustrating another example of the positional relation in the refrigerator mounting a hermetic compressor. 
           [0044]      FIG. 33  is a view illustrating an example of a configuration of a heat pump unit in a heat pump water heater. 
           [0045]      FIG. 34  is a view illustrating another example of the configuration of the heat pump unit in a heat pump water heater. 
           [0046]      FIG. 35  is a view illustrating a configuration example of an outdoor unit of an air conditioner. 
           [0047]      FIG. 36  is a view illustrating a configuration example of a show case having freezing/refrigerating functions. 
           [0048]      FIG. 37  is a view illustrating a configuration example of a condensing unit. 
           [0049]      FIG. 38  is a view illustrating a configuration example a vehicle air conditioner disposed on a ceiling of a railway vehicle. 
           [0050]      FIG. 39  is a view illustrating a configuration example of an automobile mounting a hermetic compressor for in-vehicle air conditioning. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0051]    With reference to attached drawings, embodiments of a linear motor according the present invention and an apparatus using the linear motor will be described below. In each embodiment, same components are denoted by same reference signs, and similar descriptions are not repeated. Each component in the present invention is not necessarily independently arranged. Multiple components may be formed as one member, one component may be formed by a plurality of members, a component may be a part of another component, and a part of a component and a part of another component may be overlapped. 
       First Embodiment 
       [0052]    &lt;Overall Configuration of Linear Motor&gt; 
         [0053]    With reference to  FIGS. 1 to 13 , a linear motor according to a first embodiment will be described. Hereinafter, X, Y, and Z directions indicate directions as indicated in the drawings. Further, in the case where the X direction, the Y direction, and the Z direction are respectively called a lateral direction, a vertical direction, and a longitudinal direction, the vertical direction is not necessarily parallel with the gravity direction. For example, the lateral direction, the longitudinal direction, and the other directions may be in parallel with the gravity direction. 
         [0054]    In the first embodiment, a three-phase motor is formed, and a stator includes three armatures  100 ,  101 , and  102 . Unless otherwise noted, the armatures  101  and  102  can have a same configuration as with the armature  100 . In the embodiment, although magnetic directions  51  of adjacent permanent magnets  5  are opposite each other, the magnetic directions  51  may be opposite for each of a plurality of the permanent magnets  5 . In the linear motor, moving elements including a plurality of permanent magnets  5  held by a permanent magnet holding member relatively linearly move (horizontally move) in a longitudinal direction with the armature  100 . A three-phase linear motor can be formed by disposing three armatures  100 ,  101 , and  102  such that each of the phases is electrically shifted at 120°. Similarly, m armatures form a m-phase driving linear motor. 
         [0055]    The permanent magnet  5  is fixed to the permanent magnet holding member  52  holding the permanent magnet  5 , and the permanent magnet  5  and the permanent magnet holding member  52  form a moving element. The moving element and a stator are held by a supporting means capable of a relative linear movement. The moving element and the stator at least relatively move, and it is possible to move a stator (armature) side by fixing the moving element. Further, the moving element according to the embodiment has a plane shape with a predetermined width in a lateral direction. 
         [0056]    In the armatures  100 , two magnetic pole tooth pairs including two magnetic pole teeth  11  and  12  disposed opposite to each other via a space in a vertical direction are adjacently arranged in a longitudinal direction. Specifically, the armature  100  includes a first magnetic pole tooth pair and a second magnetic pole tooth pair. The first magnetic pole tooth pair includes an upper magnetic pole tooth  11   a  and a lower magnetic pole tooth  12   a  disposed opposite to each other via a space in a vertical direction. The second magnetic pole tooth pair includes an upper magnetic pole tooth  11   b  and a lower magnetic pole tooth  12   b.  The first magnetic pole tooth pair and the second magnetic pole tooth pair are arranged in a longitudinal direction. The upper magnetic pole tooth  11   a  and the lower magnetic pole tooth  12   a  of the first magnetic pole tooth pair are connected by a magnetic material  13 , and a magnetic circuit is formed. Similarly, the upper magnetic pole tooth  11   b  and the lower magnetic pole tooth  12   b  of the second magnetic pole tooth pair are connected by the magnetic material  13 , and a magnetic circuit is formed. In addition, the first magnetic pole tooth pair and the second magnetic pole tooth pair are connected by the magnetic material  13 , and a magnetic circuit is formed. In other words, a magnetic circuit is formed which includes the upper magnetic pole tooth  11   a  and the lower magnetic pole tooth  12   a  of the first magnetic pole tooth pair, the upper magnetic pole tooth  11   b  and the lower magnetic pole tooth  12   b  of the second magnetic pole tooth pair, and the magnetic material  13 . Accordingly, a three-dimensional magnetic circuit to be described later is formed. The magnetic material  13  at least can form a magnetic circuit by forming a path through which a magnetic flux passes, and the magnetic material  13  is not necessarily integrated. Further, in the magnetic material  13  connecting magnetic pole teeth, the entire magnetic material is not necessarily a magnetic material. The magnetic material  13  at least can form a magnet circuit by forming a path through which a magnetic flux passes. 
         [0057]    Each of the magnetic pole teeth  11  and  12  has a flat shape with a substantially same vertical. Each of the magnetic pole teeth  11  and  12  has a flat shape with substantially same vertical dimension. Therefore, preferably, a winding  2  can be easily wound around and fixed to each magnetic pole tooth, and also an armature can be easily formed by lamination of electromagnetic steel sheets. As illustrated in a sectional view in  FIG. 2 , the armature  100  according to the embodiment has a shape such that two substantial “recessed” magnetic materials are disposed opposite to each other. 
         [0058]    A first winding  2   a  which is an exciting means is wound around each magnetic pole tooth of the first magnetic pole tooth pair. Similarly, a second winding  2   b  which is an exciting means is wound around each magnetic pole tooth of the second magnetic pole tooth pair. Both of two magnetic pole teeth of the magnetic pole tooth pairs according to the embodiment include windings, and the winding may be included in either one. A moving element including the permanent magnet  5  and a stator including the magnetic material  13  relatively move through a space in which the upper magnetic pole tooth  11  and the lower magnetic pole tooth  12  are disposed opposite to each other. 
         [0059]    &lt;Path of Magnetic Flux&gt; 
         [0060]    A direction of a magnetic flux formed by the first winding  2   a  and the second winding  2   b  in a space between the first magnetic pole tooth pair and a space between the second magnetic pole tooth pairs is indicated by a white arrow in  FIG. 4  (generally, a linear motor temporally changes a size and a direction of a current flowed in a winding depending on a position of a permanent magnet.  FIG. 4  indicates a magnetic flux formed in a space by a current flowed in the first winding  2   a  and the second winding  2   b  at a certain time). 
         [0061]    As indicated by the white arrow in  FIG. 4 , at a certain time, the first winding  2   a  generates an upward magnetic flux  61   a,  and the second winding  2   b  generates a downward magnetic flux  61   b.  Specifically, in the armature  100 , directions of the magnetic fluxes generated by the first winding  2   a  and the second winding  2   b  adjacent in a longitudinal direction are opposite each other. 
         [0062]    A flow of the magnetic fluxes will be described in detail with reference to  FIGS. 5 and 6 . In the embodiment, magnetic fluxes  71  and  72  generated by the first winding  2   a  and the second winding  2   b  pass through a path formed in two difference surfaces.  FIG. 5  is a view indicating directions of magnetic fluxes of the linear motor according to the embodiment at a certain time.  FIG. 6  is a perspective cross-sectional view on the YZ plane in  FIG. 5 . The magnetic flux  71  substantially passes in a surface (XY plane) orthogonal in a relative moving direction (longitudinal direction) of a stator and a moving element. The magnetic flux  72  substantially passes in a surface (YZ plane) parallel in a relative moving direction of a stator and a moving element. 
         [0063]    A detail of the above will be described below.  FIG. 10  indicates an example of the magnetic flux passing in one (a first path) of the paths formed in two different surfaces. The magnetic flux  71  generated by the first winding  2   a  and the second winding  2   b  forms a path passing through once a space between the first magnetic pole tooth pair or a space between the second magnetic pole tooth pair. With reference to  FIG. 10 , the magnetic flux  71   a  generated by the first winding  2   a  is considered as an example of the magnetic flux  71 . The magnetic flux  71   a  passes through the upper magnetic pole tooth  11   a,  the magnetic materials  13  (a magnetic material  13   a  on an upper side in the Y direction, a magnetic material  13   b  on a center side in the Y direction, and a magnetic material  13   c  on a lower side in the Y direction), the lower magnetic pole tooth  12   a,  and a space between the first magnetic pole tooth pair, and the magnetic flux  71   a  passes through a path (first path) for returning to the upper magnetic pole tooth  11   a.  Although a same path is not illustrated, the magnetic flux  71  generated by the second winding  2   b  forms a path passing through the second magnetic pole tooth pair. However, a direction of the path is opposite to a direction of the magnetic flux generated by the first winding  2   a.    
         [0064]      FIG. 11  illustrates another path (second path). A current flows in the first winding  2   a  and the second winding  2   b  in an opposite direction, and consequently a magnetic flux is generated. As a result, a path of the magnetic flux  72  is formed which passes through once each of a space between the first magnetic pole tooth pair and a space between the second magnetic pole tooth pair. The magnetic flux  72   a  which is an example of the magnetic flux  72  passes through the upper magnetic pole tooth  11   a,  the magnetic material  13   a,  the upper magnetic pole tooth  11   b,  a space between the second magnetic pole tooth pair, the lower magnetic pole tooth  12   b,  the magnetic material  13   c,  the lower magnetic pole tooth  12   a,  and a space between the first magnetic pole tooth pair, and the magnetic flux  72   a  forms a path (second path) for returning to the upper magnetic pole tooth  11   a.  In examples in  FIGS. 10 and 11 , a phase difference of currents flowing in the first winding  2   a  and the second winding  2   b  is substantially 180°, and the magnetic pole teeth  11   a  and  12   b  are an S pole, and the magnetic pole teeth  11   b  and  12   a  are an N pole. 
         [0065]    The magnetic material  13   a  connects the upper magnetic pole teeth  11   a  and  11   b  of two magnetic pole tooth pairs of the armature  100 . The magnetic material  13   c  connects the lower magnetic pole teeth  12   a  and  12   b  of two magnetic pole tooth pairs of the armature  100 . Consequently, the second path is formed. Further, the magnetic material  13   b  connects the upper magnetic pole tooth and the lower magnetic pole tooth of each magnetic pole tooth pair by connecting the magnetic materials  13   a  and  13   c.  Consequently, the first path is formed. For description, an influence on a path of a magnetic flux by the permanent magnet  5  is not considered both in the first path and the second path. 
         [0066]    By forming as described above, a three-dimensional path can be formed which includes two paths which are the first and second paths, and magnetic fluxes from the first winding  2   a  and the second winding  2   b  provided to magnetic pole teeth connected in a longitudinal direct on pass through the path. Consequently, a sectional area of the path of the magnetic fluxes is increased, and thrust can be efficiently generated. In addition, as illustrated in  FIG. 10 , magnetic path widths  70   a  and  70   b  can be reduced which are the thickness of a periphery of the armature  100  and an peripheral end of a space in which the first winding  2   a  and the second winding  2   b  are provided. Therefore, a sectional area of the linear motor illustrated in  FIG. 10  can be reduced, and a small-scale and thin linear motor can be formed. 
         [0067]    Further, in the armature  100  according to the embodiment, the winding  2  is provided to each of flat magnetic pole teeth connected by magnetic materials to form such the three-dimensional path. As a result, a magnetic flux can be efficiently used. Further, when the magnetic material is formed by using electromagnetic steel sheets, the magnetic material can be formed by steel sheets with a few shape types. Therefore, it becomes advantageous in aspects of costs and assemblability. 
         [0068]    &lt;Cooling Performance by Communication Hole&gt; 
         [0069]    In the embodiment, a communication hole  81  (refer to  FIGS. 1 and 3 ) for communicating the first winding  2   a  and the second winding  2   b  provided to the magnetic pole teeth  11  and  12  with an outer side of the armature  100  (magnetic material  13 ) is formed on a side surface of the armature  100  (surface parallel to a longitudinal direction). Preferably, the communication hole  81  is formed between two magnetic pole tooth pairs of the armature  100  in a side view. Cooling air can be supplied to the first winding  2   a  and the second winding  2   b  via the communication hole  81 , and therefore cooling performance can be improved. In addition, wire drawability of the first winding  2   a  and the second winding  2   b  can be improved by using the communication hole  81 . Regardless of whether the communication hole  81  is provided, a magnetic flux flows in accordance with a magnetic potential, and therefore motor driving according to the embodiment can be realized. 
         [0070]    In addition, an armature of each phase is independent in the linear motor according to the embodiment, and unbalance is not caused in the three-phase armature. Therefore, reduction in a thrust ripple and low detent can be realized. According to the embodiment, an apparatus can be downsized, and also a magnetic flux can be effectively shared between adjacent magnetic poles. 
         [0071]    &lt;Electric Resistance Unit&gt; 
         [0072]    A linear motor according to the embodiment includes an electric resistance unit along a longitudinal direction in the magnetic material  13  as illustrated in such as  FIG. 1 . In the embodiment, a slit  33  is provided to form an air space. The electric resistance unit can be realized by a contact resistance generated at a contact portion of same types or different types of materials provided to the magnetic material  13 . For example, the electric resistance unit is formed by surface-contacting a plurality of materials of the magnetic material. Further, a material having a larger electric resistance than the magnetic material  13  is not necessarily used. For example, even if a material having a smaller electric resistance than the magnetic material  13  is used, in consideration of such as a contact resistance, a portion is at least formed in which an electric resistance is entirely increased in a longitudinal direction of the armature  100 . 
         [0073]    In the embodiment, by providing a slit  33  along a moving direction (longitudinal direction) of a moving element as an electric resistance unit, especially, an eddy current path generated by a magnetic flux flowing in the second path can be cut or extended. Further, by changing a width or an interval of the slit, an amount of the magnetic flux  71   a  illustrated in  FIG. 10  and an amount of the magnetic flux  72   b  illustrated in  FIG. 11  can be changed. Furthermore, a surface area of the armature  100  can be increased by the slit  33 , and therefore cooling performance can be improved. Since the cooling performance is improved, a large current can flow in a winding, and the apparatus can be further downsized. In addition, as illustrated in  FIG. 12 , the magnetic materials  13  can be laminated in the Z direction. As a result, a contact surface of the magnetic material  13  can be generated along a lateral direction, and therefore an eddy current caused by a magnetic flux flowing in the first path by a contact resistance can be reduced. 
         [0074]      FIG. 13  is a view indicating an example in which an electric resistance unit such as the slit  33  is provided in a radial shape extending toward a periphery of an armature. A magnetic flux flowing to magnetic pole teeth in the first path or a magnetic flux flowing out from the magnetic pole teeth move while orbiting radially. When an electric resistance unit is provided in parallel with the YZ plane, a magnetic flux needs to avoid the electric resistance unit. As a result, a magnetic path is extended, and a loss is increased. In the embodiment, a part of or all of the slit  33  is provided along the Z direction and in non-parallel with the YZ plane, and consequently, the magnetic path length is shortened. 
       Second Embodiment 
       [0075]    &lt;Cooling Pipe&gt; 
         [0076]      FIGS. 14 to 18  indicate a second embodiment of the linear motor according to the present invention. The linear motor according to the embodiment has a same configuration as in the first embodiment other than the following points.  FIG. 14  is a perspective view of the linear motor according to the second embodiment. A magnetic material  13  includes a slit  33  as an electric resistance unit. The slit  33  includes a cooling pipe  20 . Such as cooling water can flow on an inner side of the cooling pipe  20 . By disposing the cooling pipe  20  by inserting into the slit  33 , cooling performance can be improved without increasing a dimension in an XY plane. 
         [0077]      FIG. 15  is a top view of the linear motor according to the embodiment. The cooling pipe  20  is disposed so as to penetrate a plurality of armatures  100 ,  101 , and  102 . In the embodiment, one cooling pipe  20  is disposed to a plurality (four) of slits  33  of each armature. However, the configuration is not limited even if the same effect can be obtained. For example, a plurality of the cooling pipes  20  may be provided. In this case, occurrence of a temperature difference between an upstream, side and a downstream, side of the cooling pipe  20  can be suppressed, and each armature can be equally cooled. 
         [0078]    &lt;Fixing Hole&gt; 
         [0079]      FIG. 16  is an elevation view of the linear motor in the embodiment. The magnetic material  13  includes a fixing hole  57  penetrating in a longitudinal direction. Each armature can be fixed by penetrating such as a shaft into the fixing hole  57 , and intervals between armatures can be adjusted by inserting such as a color and a spacer. In the case where the magnetic material  13  is formed by laminating such as electromagnetic steel sheets in a longitudinal direction, the magnetic material  13  needs to be fixed to avoid decomposition. By inserting such as a bolt in the fixing hole  57 , the magnetic material  13  can be fixed. while inhibiting an increase in size of the armature. Since magnetic pole teeth  11  and  12  according to the embodiment have a flat shape, shape types of the electromagnetic steel sheets to be laminated can be reduced. 
         [0080]    Further, the fixing hole  57  is preferably provided near a center in a lateral direction of the magnetic material  13 . A magnetic flux flowed in and out from the magnetic pole teeth  11  and  12  radially move. Therefore, an amount of the magnetic flux passing through near a center of the magnetic material  13  is reduced. Therefore, electromagnetic steel sheets can be fixed while preventing interference of flow of the magnetic flux. 
         [0081]    &lt;Slit Depth&gt; 
         [0082]      FIG. 17  is a view cut on a C-C cross-section in  FIG. 15 . However, the cooling pipe  20  is not illustrated in  FIG. 17 . A distance from a surface of the armature  100  (for example, a surface on an upper direction side) to an end on a surface side of the winding  2  provided on the surface side (for example, an upper side surface of the winding  2 ) is a winding depth  10 . Further, a depth of the slit  33  (a distance from one end to another end of the slit  33 ) provided on a surface of the armature  100  (for example, a surface on an upper direction side) is a slit depth  41 . In the case where the slit depth  41  is set so as to satisfy an inequality, (the slit depth  41 )&gt;(the winding depth  40 ), with respect to the winding depth  40 , the slit  33  reaches an inner side of a volume surrounded by the winding  2 . 
         [0083]    Therefore, the winding  2  can be cooled from the inner side by blowing cooling air from the outside. As a result, a limitation of a current value which can he flowed in the winding  2  is increased, and a linear motor with large thrust can be realized. Further, even if thrust is the same, downsizing can be realized. Furthermore, in the case where the inequality, (the slit depth  41 )&gt;(the winding depth  40 ), is satisfied, and the cooling pipe  20  is disposed to the slit  33 , the cooling pipe  20  can be made to contact with the winding  2 . In the case where the cooling pipe  20  is provided so as to come into contact with the winding  2 , cooling performance can be further improved. 
         [0084]    The fixing hole  57  is provided within a range from a surface of the magnetic material  13  to the winding depth  40 . As a result, the fixing hole  57  is not overlapped with the winding. 
         [0085]    Further, as illustrated in  FIG. 18 , a part of or all of the slit  33  can be inclined so as to be non-parallel with the YZ plane. As in this case, in the case where the inequality, (the slit depth  41 )&gt;(the winding depth  40 ), is satisfied, and the cooling pipe  20  is disposed to the slit  33 , the cooling pipe  20  can be made to contact with the winding  2 . 
       Third Embodiment 
       [0086]    &lt;Three-Phase Driving by One Armature&gt; 
         [0087]      FIGS. 19 to 22  indicate a third embodiment of the linear motor in the present invention. The linear motor according to the embodiment is related to three-phase driving, and a configuration thereof is similar to the configurations in the first and second embodiments other than the following points. An armature  100  according to the embodiment includes a third magnetic pole tooth pair including magnetic pole teeth  11   a   3  and  12   a   3  in addition to the first magnetic pole tooth pair including magnetic pole teeth  11   a   1  and  12   a   1  and the second magnetic pole tooth pair including magnetic pole teeth  11   a   2  and  12   a   2 , which are disposed opposite to each other in a vertical direction. The magnetic pole teeth of either or both of each magnetic pole tooth pair include a first winding  2   a,  a second winding  2   b,  and a third winding  2   c.  A phase difference of current flowing in adjacent windings, in other words, the first winding  2   a  and the second winding  2   b  and the second winding  2   b  and the third winding  2   c  is substantially 120°. As a result, U, V, and W phases can be formed by one armature  100 . In this case, at least one of the first winding  2   a,  the second winding  2   b,  and the third winding  2   c  supplies a magnetic flux in an opposite direction with the other two windings  2 . The armature  100  includes two communication holes  81   a  and  81   b  as a communication hole  81 . From a viewpoint of cooling performance, it is preferable that the communication holes  81   a  and  81   b  are respectively provided between the first magnetic pole tooth pair and the second magnetic pole tooth pair and between the second magnetic pole tooth pair and the third magnetic pole tooth pair in a side view. Regardless of whether the communication hole  81  is provided, a magnetic flux flows in accordance with a magnetic potential, and therefore the three-phase driving according to the embodiment can be realized. As configured in this manner, the three-phase driving can be realized by one armature  100 . As illustrated in  FIG. 19 , a first path which is a path of a magnetic flux  71  passing through any of the magnetic pole tooth pairs is formed. Further, as illustrated in  FIG. 20( a ) , as a second path, two paths passing through two magnetic pole tooth pairs is formed at each time. Therefore, the same effects as in the first embodiment can be obtained. In the embodiment, two permanent magnets  5  are adjacently arranged to moving elements with respect to three magnetic pole tooth pairs of the armature  100 . In this manner, as illustrated in  FIG. 20( b ) , a linear motor is driven when a U-phase current flows in the first winding  2   a,  a V-phase current flows in the second winding  2   b,  and a W-phase current flows in the third winding  2   c.    
         [0088]    &lt;Three-Phase Driving by Multiple Armatures&gt; 
         [0089]    As described in such as the first embodiment, the U, V, and W phases can be realized by separate armatures  100 ,  101 , and  102  respectively (refer to  FIGS. 21 and 22 ). In each winding  2  of the armatures of the U, V, and W phases, an electrical phase difference between the U phase and the V phase is approximately 120°, and an electrical phase difference between the V phase and the W phase is approximately 120°. The armatures  100 ,  101 , and  102  each forming the second path includes two magnetic pole tooth pairs in a longitudinal direction. Each phase difference of two magnetic pole tooth pairs of each phase is approximately 180°. Specifically, the winding  2  provided to each of two magnetic pole tooth pairs included in each armature supply magnetic fluxes in an opposite direction. 
         [0090]      FIG. 22  indicates an arrangement of each phase. In the embodiment, the windings  2  are arranged in the order of U+, U−, V−, V+, W+, and W− phases. Each of phase differences of the U+, V+, and W+ phases are substantially 120°, and each of phase differences between the U+ and U− phases, the V+ and V− phases, and the W+ and W− phases is approximately 180°. As illustrated in  FIG. 22 , the + side and the − side of each phase are adjacent. In the case of forming three-phase driving in this manner, for example, five or seven permanent magnets can be arranged to a moving element with respect to six magnetic pole tooth pairs arranged in a longitudinal direction. The first winding  2   a  and the second winding  2   b  are set such that an electrical phase difference shifts at substantially 180°, and directions of magnetic fluxes formed by the first winding  2   a  and the second winding  2   b  are opposite each other in a vertical direction. Consequently, a second path is formed. 
         [0091]    In the case where separate armatures form three phases as described above, magnetic interference among the phases can be suppressed. Therefore, end effects caused by an end armature of a linear motor and an armature disposed so as to be sandwiched by armatures can be reduced, and a thrust ripple can be reduced. 
       Fourth Embodiment 
       [0092]    &lt;Stator Relatively Moving with Multiple Moving Elements&gt; 
         [0093]      FIGS. 23 to 25  indicate a fourth embodiment of the linear motor according to the present invention.  FIG. 23  is a perspective view of the linear motor according to the fourth embodiment, and  FIG. 24  is a side sectional view of the linear motor according to the embodiment. The linear motor according to the embodiment has a same configuration as in the first to third embodiments other than the following points. The linear motor according to the embodiment includes multiple moving elements in a vertical direction orthogonal to a longitudinal direction which is a moving direction of the moving elements. As a result, the linear motor can be downsized. As illustrated in  FIGS. 23 and 24 , the linear motor according to the embodiment includes two moving elements arranged in the Y direction. For description, a moving element on an upper side of the Y direction is called “an upper moving element”, and a moving element on a lower side is called “a lower moving element”. 
         [0094]    At least one or more armatures are disposed in the longitudinal direction, and also two or more moving elements are arranged in the vertical direction. 
         [0095]      FIG. 25  is an elevational sectional view of the linear motor according to the embodiment illustrated in  FIGS. 23 and 24  and indicates a path of a magnetic flux by arrows. 
         [0096]    An armature  100  according to the fourth embodiment includes, as illustrated in  FIG. 25 , an upper first magnetic pole tooth pair and a lower first magnetic pole tooth pair. The upper first magnetic pole tooth pair includes magnetic pole teeth  11   a  and  12   a  disposed opposite to each other via a space in which the upper moving element relatively moves. The lower first magnetic pole tooth pair includes a magnetic pole teeth  11   b  and  12   b  disposed opposite to each other via a space into which the lower moving element moves. In addition, the armatures  100  according to the embodiment includes an upper second magnetic pole tooth pair and a lower second magnetic pole tooth pair so as to be disposed in a longitudinal direction of the upper first magnetic pole tooth pair and the lower first magnetic pole tooth pair, respectively. The four magnetic pole tooth pairs are connected by a magnetic material  13  and form a magnetic circuit. In magnetic circuits of the upper first magnetic pole tooth pair and the lower first magnetic pole tooth pair and magnetic circuits of the upper second magnetic pole tooth pair and the lower second magnetic pole tooth pair, a first path is formed by the same configuration. Therefore, the upper first magnetic pole tooth pair and the lower first magnetic pole tooth pair illustrated in  FIG. 25  are representatively described. Magnetic pole teeth have a substantially same shape, and also an upper third magnetic pole tooth pair and a lower third magnetic pole tooth pair may be included. 
         [0097]    Further, for description, the magnetic pole teeth  11   a  and  12   b  disposed outermost in a vertical direction of the armature  100  is denoted as outside magnetic pole teeth  11   a  and  12   b . Further, the magnetic pole teeth  12   a  and  11   b  which are not disposed outermost in the vertical direction of the armature  100  is denoted as inside magnetic pole teeth  12   a  and  11   b.    
         [0098]    The outside magnetic pole teeth  11   a  and  12   b  are connected by an outside magnetic material  13   a.  The inside magnetic pole teeth  12   a  and  11   b  are connected by an inside magnetic material  13   b.  Further, the outside magnetic material  13   a  and the inside magnetic material  13   b  are connected by an iron core connecting portion  58 . The iron core connecting portion  58  is a magnetic material of a magnetic path width  70   c  supporting the inside magnetic material  13   b.    
         [0099]    A first winding  2   a  and a second winding  2   d  of the armature  100  are arranged in a vertical direction, and magnetic fluxes supplied by the windings face in the same direction. In this manner, both of the magnetic fluxes supplied by the first winding  2   a  and the second winding  2   d  pass through the outside magnetic material  13   a,  the outside magnetic pole tooth  12   b,  the inside magnetic pole tooth  11   b,  the inside magnetic material  13   b,  the inside magnetic pole tooth  12   a,  and the outside magnetic pole tooth  11   a.  Specifically, magnetic flux by each winding passes through both of the upper and lower magnetic pole tooth pairs, and therefore a thrust efficiency with respect to moving elements is improved. Further, a part of the magnetic flux flows in the iron core connecting portion  58 . However, this magnetic flux is cancelled. Therefore, the magnetic path width  70   c  which is a width in a vertical direction of the iron core connecting portion  58  can be narrowed in comparison with the magnetic path width  70   a  which is a length from a surface of the outside magnetic material  13   a  to a surface side of the winding  2 . 
         [0100]    For comparison, the case where the armatures  100  according to the first embodiment are vertically laminated (the case where vertical magnetic circuits are independently arranged) is considered. In this case, the sum of the height of a magnetic material disposed lower than a moving element in an armature on an upper stage and the height of a magnetic material disposed higher than a moving element in an armature on a lower stage is needed to be the height corresponding to twice of the magnetic path width  70   a.  On the other hand, as in the embodiment, in the case where the armature  100  moves relatively with a plurality of moving elements  6 , a magnetic flux flowing in the iron core connecting portion  58  is cancelled. Therefore, the magnetic path width  70   c  can be narrowed in comparison with the magnetic path width  70   a.  Specifically, (the magnetic path width  70   a )&gt;(the magnetic path width  70   c ) is established. 
         [0101]    As a result, a height in the Y direction of a linear motor can be reduced, and a small scale linear motor can be provided. The magnetic path width  70   a  and the magnetic path width  70   c  are equal to or larger than the length in a vertical direction of a fixing hole  57 . By forming in this manner, preferably, the magnetic material  13  can be formed by laminating electromagnetic steel sheets in a longitudinal direction, and a bolt can be inserted into the fixing hole  57 . 
         [0102]    Although an example of two moving elements has been described in the fourth embodiment, similar effects may be obtained by three or more moving elements. Further, downsizing the linear motor according to the embodiment can be realized by the magnetic path width  70   c  which can be formed by including two or more magnetic pole tooth pairs in a vertical direction. Therefore, two or more magnetic pole teeth are not necessarily arranged in the vertical direction, and one magnetic pole tooth may be arranged in a longitudinal direction. 
       Fifth Embodiment 
       [0103]    &lt;Module Configuration by Outside Parts and Inside Parts&gt; 
         [0104]      FIGS. 26( a ) to 26( d )  indicate a fifth embodiment of the linear motor according to the present invention. The linear motor according to the fifth embodiment has a same configuration as in the first to fourth embodiments other than the following points. In the embodiment, a magnetic material  13  can be divided into two-type combinations of outside parts  13   a  and inside parts  13   b.  As an example,  FIG. 26( a )  is an elevational sectional view of a linear motor in which four moving elements are arranged in the Y direction. In the embodiment, directions of magnetic fluxes formed by windings  2   a  to  2   h  are the same. By increasing a number of stages, a number ratio of the magnetic path width  70   c  with respect to the magnetic path width  70   a  is increased. Therefore, a small scale linear motor can be formed. Further, the magnetic flux formed by each of the windings  2   a  to  2   h  passes through each of magnetic pole tooth pairs. Therefore, thrust of the linear motor can be further increased by interaction. 
         [0105]    The outside parts  13   a  is an outermost periphery of the armature  100  illustrated in  FIG. 26( a )  and is a magnetic material including two outside magnetic pole teeth  11   a  disposed in an uppermost portion in a longitudinal direction. Further, a magnetic material including adjacent two outside magnetic pole teeth  12   d  disposed in the lowest portion in a longitudinal direction is also the outside parts  13   a,  and the magnetic materials have a substantially same shape. Hereinafter, the outside magnetic pole tooth is representatively denoted by  11   a . As illustrated in  FIGS. 26( c ) and 26( d ) , the outside parts  13   a  may be a magnetic material including three or more adjacent outside magnetic pole teeth  11   a  in a longitudinal direction and may be a magnetic material including one outside magnetic pole tooth  11   a  in a longitudinal direction (not illustrated). 
         [0106]    The outside parts  13   a  includes an iron core  7   e   1  vertically extending in a lateral direction of the outside magnetic pole tooth  11   a.  The outside parts  13   a  connects to the iron core  7   e   1  by an iron core connecting portion of the magnetic path width  70   a.  A connecting portion  45  to be described later is included at a tip of the iron core  7   e   1 . 
         [0107]    The inside parts  13   b  is a magnetic material including two lower magnetic pole teeth  12   a  and two upper magnetic pole teeth  11   b  which are adjacently arranged in a longitudinal direction. Further, the inside parts includes a magnetic material including two lower magnetic pole teeth  12   b  and two upper magnetic pole teeth  11   c  adjacently arranged in a longitudinal direction and a magnetic material including two lower magnetic pole teeth  12   c  and two upper magnetic pole teeth  11   d,  and these have a substantially same shape. Hereinafter, the lower magnetic pole tooth is representatively denoted by  12   a,  and the upper magnetic pole tooth is representatively denoted by As illustrated in  FIGS. 26( c ) and 26( d ) , a magnetic material may include three or more lower magnetic pole tooth  12  and three or more upper magnetic pole tooth  11  adjacently arranged in a longitudinal direction and may be a magnetic material including one outside magnetic pole teeth  11   a  in a longitudinal direction (not illustrated). 
         [0108]    Regarding the inside parts  13   b,  two lower magnetic pole teeth  12   a  and two upper magnetic pole teeth  11   b  are disposed opposite to each other in a vertical direction. Further, the inside parts  13   b  includes a vertically extending iron core  7   e   2  in a lateral direction of the lower magnetic pole tooth  12   a  and the upper magnetic pole tooth  11   b.  The inside parts  13   b  connects to the iron core  7   e   2  by an iron core connecting portion of the magnetic path width  70   c.  A connecting portion  45  to be described later is included at two tips of the iron core  7   e   2 . These four magnetic pole teeth form a part of or all of a magnetic circuit by being connected by a magnetic material. 
         [0109]    A vertical length of the fixing hole  57  of the inside parts is set to smaller than a vertical length (magnetic path width)  70   c  of the iron core connecting portion. As a result, it is prevented that the winding  2  is overlapped with the fixing hole  57 , and assemblability can be improved. Further, as described above, the fixing hole  57  is preferably provided near a center in a lateral direction. A shape of the fixing hole  57  may be a flat shape in the lateral direction. In this case, the inside parts can be fixed while minimizing the magnetic path width  70   c . The magnetic path width  70   c  at least sufficiently supports a portion where the lower magnetic pole tooth  12   a  and the upper magnetic pole tooth  11   b  of the inner parts are provided. 
         [0110]    By combining and connecting the outside parts  13   a  and the inside parts  13   b,  the magnetic material  13  and a magnetic pole tooth pair of the armature  100  can be formed. Specifically, in the embodiment, parts forming a magnetic path can be formed by magnetic materials  13   a  and  13   b  having two-type shapes. In the case where the outside parts and the inside parts are formed by laminating electromagnetic steel sheets, since a magnetic pole tooth is flat, the parts can be formed by using a few types of steel sheets. 
         [0111]    &lt;Connecting Portion&gt; 
         [0112]    Each of the outside parts  13   a  and the inside parts  13   b  include a connecting portion  45 . The outside parts  13   a  and the inside parts  13   b  or the inside parts  13   b  each other can be connected by the connecting portion  45 . With reference to  FIGS. 26( a ) to 26( d ) , the connecting portion will be described in detail later. The outside parts  13   a  and the inside parts  13   b  include either or both of a first-shape connecting portion and a second-shape connecting portion which can fit each other as the connecting portion  45 . In the embodiment, the outside parts  13   a  and the inside parts  13   b  include both of a projected line connecting portion  45   a  as the first-shape connecting portion and a recessed line connecting portion  45   b  as the second-shape connecting portion. By connecting the two parts, a member including magnetic pole tooth pairs disposed opposite to each other via a space is formed. Specifically, a region can be formed in which one moving element can drive. 
         [0113]    The outside parts  13   a  according to the embodiment can be connected to both of a first surface and a second surface of the inside parts  13   a.  Further, each of a first surface and a second surface of the inside parts can be connected to the first surface and the second surface of the other inside parts  13   a . Furthermore, the outside parts  13   b  can be connected each other. 
         [0114]    As described above, the magnetic material  13  and a magnetic pole tooth pair of the armature  100  can be formed by combining and connecting two outside parts  13   a  and one or more or two or more inside parts  13   b.    
         [0115]    Therefore, by adjusting a number of the inside parts  13   b  forming the armature  100 , a number of moving elements of a linear motor can be easily adjusted. As a result, a user determines a number of the moving elements included in the linear motor. 
         [0116]    A linear motor having different thrust (a number of stages of moving elements of a linear motor) by a multistage configuration by using a few types of parts can be provided as the linear motor according to the embodiment. Therefore, a production line can be shared, and time and costs for parts design can be significantly reduced. Further, a number of the inner peripheral magnetic path widths  70   c,  which is narrower than the outermost peripheral magnetic path width  70   a,  is increased. Therefore, while obtaining large thrust by the multistage configuration, downsizing can be realized. 
         [0117]    &lt;Projected and Recessed Line Connecting Portion&gt; 
         [0118]      FIG. 26( b )  is an enlarged view of a projected line connecting portion  45   a  and a recessed line connecting portion  45   b.  Connection between parts can be simplified by the connecting portion  45 , and productivity when a linear motor is assembled is improved. The connecting portions are a projected line shape and a recessed line shape. Therefore, when the outside parts and the inside parts are manufactured by using such as laminated steel plates, a number of types of the steel plates can be minimized. Specifically, by laminating a plurality of steel plates including projected connecting portions and recessed connecting portions, a projected line connecting portion and a recessed line connecting portion are formed. 
         [0119]    The connecting portion  45  has a same shape along a longitudinal direction and is not especially limited in the case where the shapes are formed in two types which can fit each other. 
         [0120]    &lt;Symmetry&gt; 
         [0121]    The outside parts  13   a  and the inside parts  13   b  are substantially rectangular shape in a plan view (Y direction view), and the projected line connecting portion  45   a  and the recessed line connecting portion  45   b  are included on the outside of magnetic pole teeth. Further, the inside parts  13   b  includes the projected line connecting portion  45   a  and the recessed line connecting portion  45   b  on the outside of a magnetic pole tooth and includes the projected connecting portion  45   a  and the recessed connecting portion  45   b  on the outside of a magnetic pole tooth disposed on an opposite side of the above magnetic pole tooth. More specifically, types of the connecting portions  45  adjacent in a vertical direction or a lateral direction are different, and types of the connecting portions  45  disposed diagonally opposite are the same. As a result, the inside parts  13   b  other than the connecting portion  45  is dyad symmetry when a lateral direction, a vertical direction, and a longitudinal direction are a rotation axis. Specifically, when the inside parts  13   b  is half rotated around any of the X, Y, and Z axes, the inside parts  13   b  other than the connecting portion  45  have a substantially same shape as an original shape. A type of the connecting portion  45  is changed by half-rotation. For example, when the inside parts  13   b  according to the embodiment is half rotated around the Y axis, the recessed connecting portion  45   b  is positioned where the projected connecting portion  45   a  has been positioned before the half rotation, and the projected connecting portion  45   a  is positioned where the recessed connecting portion  45   b  has been positioned. Specifically, in the case where the inside parts  13   b  according to the embodiment is half rotated around a predetermined axis, a shape of the parts before and after the half rotation are substantially same. Further, before and after the rotation, a position of the projected connecting portion  45   a  and a position of the recessed connecting portion  45   b  are exchanged. The position exchange by the half rotation around the X axis is because types of the connecting portions  45  adjacent in a vertical direction are different. The position exchange by the half rotation around the Y axis is because types of the connecting portions  45  adjacent in a lateral direction. are different. 
         [0122]    The outside parts  13   a  other than the connecting portion  45  is also dyad symmetry when the vertical (Y) direction is a rotation axis. Further, since types of the connecting portions  45  adjacent in a lateral direction are different, the types of the connecting portion  45  are exchanged by half-rotating around the Y axis. 
         [0123]    Specifically, in the embodiment, in the case where a person who assembles holds two parts in a direction in which the connecting portions  45  of the parts are not corresponding each other when connecting the two parts, types of the connecting portions  45  positioned at the same portion can be changed by half-rotating around a predetermined axis. As a result, assemblability can be improved. 
         [0124]    &lt;Relation of Number of Turns of Winding&gt; 
         [0125]    Each of vertically arranged windings  2  supplies magnetic flux in a same direction. Here, in each of the magnetic pole teeth  11  and  12  disposed in a vertical direction of the armature  100  according to the embodiment illustrated in  FIG. 26( a ) , a sum of a number of turns of the windings  2   a,    2   b,    2   c , and  2   d  provided on an upper side from a center is preferably substantially equal to a sum of a number of turns of the windings  2   e,    2   f,    2   g,  and  2   h  provided on a lower side from the center in the vertical direction. In other words, the armature  100  according to the embodiment includes four magnetic pole tooth pairs and therefore includes 2×4 magnetic pole teeth, specifically total eight magnetic pole teeth. Therefore, a number of turns of windings wound around first to fourth four magnetic pole teeth from an uppermost stage and a number of turns of windings wound around the other four magnetic pole teeth are preferably substantially equal. In this manner, it becomes easy to balance vertical forces applied to each moving element. 
         [0126]    Further in general, when a number of the magnetic pole teeth arranged in a vertical direction is 2n (n is a positive integer), a number of turns of windings around total n magnetic pole teeth counted downward from the uppermost magnetic tooth of an armature and a total number of turns of windings around the other n magnetic pole tooth are substantially equal. In consideration of multistage configuration according to the embodiment, “n” is preferably an integer of 2 or lager. 
         [0127]    Further, a number of turns of the windings  2   a,    2   c,    2   e , and  2   g  provided to upper magnetic pole teeth of a magnetic pole tooth pair according to the embodiment are preferably substantially equal to numbers of turns of the windings  2   b,    2   d ,  2   f,  and  2   h  provided to lower magnetic pole teeth of the magnetic pole tooth pair, respectively. In this manner, it becomes easy to balance vertical forces applied to each moving element. 
         [0128]    A number of turns may be counted actually, may measure a length of a winding by linearly extending the winding, or may convert to a ratio of the length by measuring electric resistance. 
         [0129]    A plurality of moving elements arranged in a vertical direction may be mechanically connected. For example, a plurality of the moving elements can be connected by providing a connecting portion at longitudinal ends of a moving element. In this case, all of the moving elements may be connected and may be symmetrically connected in a vertical direction. Symmetrically connecting in a vertical direction means, for example, connecting ath moving element, and (M−a+1)th moving element when moving elements are numbered as 1, 2, . . . M from the top. However, “a” is an integer of 1&lt;a&lt;(M/2). 
       Sixth Embodiment 
       [0130]      FIG. 27  indicates a sixth embodiment of the linear motor according to the present invention. The linear motor according to the sixth embodiment has a same configuration as in the first to fifth embodiments other than the following points. The linear motor according to the embodiment is a linear motor capable of three-phase driving by one armature and indicates an example in which upper magnetic pole teeth, lower magnetic pole teeth, a magnetic material for connecting the lower magnetic pole teeth and the upper magnetic pole teeth are formed by using laminated steel sheets. By adjusting a number of laminated steel sheets, a thickness in the Z direction of a magnetic pole tooth can be changed. Further, by changing the thickness in the Z direction of the magnetic pole tooth by changing a pitch and a size of a permanent magnet  5  and a permanent magnet of a permanent magnet holding member  52 , a design in which an induced voltage generated to a winding by thrust and a magnet is changed can be realized by adjusting a number of laminated steel sheets. 
       Seventh Embodiment 
       [0131]      FIG. 28  indicates a seventh embodiment of the linear motor according to the present invention. The linear motor according to the seventh embodiment has a same configuration as in the first to sixth embodiments other than the following points. The linear motor according to the embodiment is a linear motor capable of three-phase driving by three armatures and is an example in which upper magnetic pole teeth, lower magnetic pole teeth, and a magnetic material connecting the upper magnetic pole teeth and the lower magnetic pole teeth and forming a path of a magnetic flux are formed by using laminated steel sheets. In the example, a magnetic material  13   a  for connecting magnetic pole teeth adjacently disposed in the Z direction is integrally formed with the magnetic pole teeth. In the example, the magnetic pole teeth and the magnetic material  13   a  are integrated to avoid decomposition of parts of the magnetic material  13   a  by a slit  33 . According to this configuration, a number of parts can be reduced. 
       Eighth Embodiment 
       [0132]      FIGS. 29 and 30  indicate a seventh embodiment of the linear motor according to the present invention. The linear motor according to the eighth embodiment has a same configuration as in the first to seventh embodiments other than the following points. The embodiment indicates an example that a magnetic material connecting upper magnetic pole teeth and lower magnetic pole teeth and forming a path of a magnetic flux forms the path of the magnetic flux on one side of a moving element (an upper direction on the drawing according to the embodiment). As described above, moving elements are fixed to such as a base  53 , and an armature side can be moved, by providing a magnetic material connecting upper magnetic pole teeth and lower magnetic pole teeth and forming a path of a magnetic flux on one side. 
       Ninth Embodiment 
       [0133]    In the ninth embodiment, as an example of an apparatus using the linear motor according to the present invention, a hermetic compressor  350  and a refrigerator mounting the hermetic compressor  350  are indicated. 
         [0134]      FIGS. 31 and 32  are a schematic sectional view of a refrigerator  360  mounting the hermetic compressor  350  including the linear motor according to the embodiment. The refrigerator  360  includes a refrigeration chamber  362 , an upper freezing chamber  363 , a lower freezing chamber  364 , a vegetable chamber  365 , and a machine chamber  367 . The hermetic compressor  350  is disposed in the machine chamber  367 . A positional relation of the refrigeration chamber  362 , the upper freezing chamber  363 , the lower freezing chamber  364 , the vegetable chamber  365 , and the machine chamber  367  is not limited to  FIGS. 31 and 32 . A height dimension Hc of the hermetic compressor  350  can be designed low. Therefore, as illustrated in  FIG. 31 , in the case where the hermetic compressor  350  is disposed such that a height direction of the hermetic compressor  350  comes to the gravity direction, a height dimension Hm of the machine chamber  367  can be reduced, and a volume of the vegetable chamber  365  can be increased. 
         [0135]    Further, as illustrated in  FIG. 32 , in the case where the hermetic compressor  350  is disposed such that a height direction of the hermetic compressor  350  comes to a horizontal direction, a width dimension Wm of the machine chamber  367  can be reduced, and a volume of the vegetable chamber  365  can be increased. 
         [0136]    Furthermore, the hermetic compressor  350  is disposed on a rear side of the vegetable chamber  365 . However, in the case where the hermetic compressor  350  is disposed on such as a rear side of the refrigeration chamber  362  which is different from the above, a space in the freezing device can be effectively used according to the embodiment in which the height dimension Hc of the hermetic compressor  350  can be designed low. 
         [0137]    As described above, in the case where the hermetic compressor  350  according to the embodiment is used in the freezing device such as a refrigeration chamber, since the hermetic compressor  350  is a small size, a storage space of the freezing device can be increased without changing a size of the freezing device. Further, by downsizing the freezing device, a space can be saved. 
       Tenth Embodiment 
       [0138]    In the tenth embodiment, as an example of an apparatus mounting a linear motor according to the present invention, a heat pump mounts a hermetic compressor  350 .  FIGS. 33 and 34  are a schematic view of a heat pump unit  385  in a heat pump water heater. The heat pump unit  385  includes the hermetic compressor  350  mounting the linear motor indicated in the embodiment, a fan  382 , a heat exchanger  380 , and a water heater heat exchanger  381 . A refrigerant compressed by the hermetic compressor  350  heats water by the water heater heat exchanger  381 , passes through an inflation valve (not illustrated), evaporates in the heat exchanger  380 , and returns to the hermetic compressor  350 . The water heater heat exchanger  381  may be disposed beside the fan  382  or on a lower side of the fan  382  as illustrated in FIG.  33 . 
         [0139]    In the case where the hermetic compressor  350  according to the embodiment is used in the heat pump unit  385 , a size of the heat pump unit  385  can be reduced by the principal in the case of using the hermetic compressor  350  in the refrigerator  360 . Further, by using that the height dimension Hc of the hermetic compressor  350  is small, the dimension of the heat exchanger  380  and the water heater heat exchanger  381  can be increased without changing an external dimension of the heat pump unit  385 . Therefore, the heat exchanger  380  and the water heater heat exchanger  381  can be further freely designed and can be efficiently designed. 
       Eleventh Embodiment 
       [0140]    In an eleventh embodiment, as an example of an apparatus mounting the linear motor according to the present invention, an air conditioner mounting a hermetic compressor  350  is indicated.  FIG. 35  is a schematic view of an outdoor unit  386  of the air conditioner. The outdoor unit  386  includes the hermetic compressor  350 , a fan  382 , and a heat exchanger  380 . In  FIG. 35 , the hermetic compressor  350  is disposed on a lower side of the fan  382 . However, a positional relation between the hermetic compressor  350  and the fan  382  are not limited thereto. 
         [0141]    In the case where the hermetic compressor  350  is used in an air conditioner, since the hermetic compressor  350  is a small size, a dimension of the outdoor unit  386  can be reduced. Further, as in the case where the hermetic compressor is used in a heat pump unit  385 , a dimension of the heat exchanger  380  can be increased without changing a dimension of the outside unit  386 . Therefore, the heat exchanger  380  can be further freely designed and further efficiently designed. 
       Twelfth Embodiment 
       [0142]    In an twelfth embodiment, as an example of an apparatus mounting the linear motor according to the present invention, a showcase mounting a hermetic compressor  350  is indicated.  FIG. 36  is a schematic view of a show case  390  having freezing and refrigerating functions. A condensing unit  391  is disposed on a lower side of a product shelf  392 , and an evaporator  393  is arranged on a back surface of a show case  390 . Air cooled by the evaporator  393  is sent to the product shelf  392  from a cooling air duct  395 .  FIG. 37  is a schematic configuration view of the condensing unit  391 . The condensing unit  391  includes the hermetic compressor  350 , a heat exchanger  396 , a fan  397 , an electric component box  398 , and an accumulator  399 . 
         [0143]    When the hermetic compressor  350  is especially small in a height direction, the overall height of the condensing unit  391  can be lowered. Therefore, without changing a dimension of the show case  390 , a height dimension of the product shelf  392  can be increased. Further, when the hermetic compressor  350  is a small size, the inside of the condensing unit  391  is ventilated, and heat can be efficiently exchanged by the heat exchanger  396 . 
       Thirteenth Embodiment 
       [0144]    In a thirteenth embodiment, as an example of an apparatus mounting the linear motor according to the present invention, a vehicle air conditioner mounting a hermetic compressor  350  is indicated.  FIG. 38  is a schematic view of a vehicle air conditioner  405  disposed on a ceiling of a railway vehicle  400 . The vehicle air conditioner  405  includes the hermetic compressor  350 , an outdoor side heat exchanger  403 , an outdoor side fan  404 , an indoor side heat exchanger  401 , and an indoor side fan  402 . Since the hermetic compressor  350  is a small size, especially can be downsized in a height direction, the overall height of the vehicle air conditioner  405  can be reduced. The overall height of the vehicle air conditioner  405  is preferably low from the viewpoint of air resistance of the railway vehicle  400 . Further, in the case of the railway vehicle  400  traveling in a tunnel such as underground, in consideration of a restriction in a height direction of the tunnel, a cabin space can be widened when the overall height of the vehicle air conditioner  405  is low. Further, when the hermetic compressor  350  is a small size, the inside of the vehicle air conditioner  405  is ventilated, and heat can be efficiently exchanged by the outdoor side heat exchanger  403 . 
       Fourteenth Embodiment 
       [0145]    In a fourteenth embodiment, as an example of an apparatus mounting the linear motor according to the present invention, an automobile mounting a hermetic compressor  350  is indicated.  FIG. 39  is a schematic view of an automobile  410  mounting the hermetic compressor  350  for in-vehicle air conditioning. A setting position of the hermetic compressor  350  is not limited to the above. When the hermetic compressor  350  is a small size, the automobile  410  in which a cabin space is widened can be designed. 
         [0146]    In the first to fourth embodiments of the present invention, a space for passing through such as a winding wire is provided on a side of an armature. However, the present invention is not limited by whether or not to provide the hole. 
         [0147]    In the first to seventh embodiments according to the invention, a magnetic material connecting an upper magnetic pole tooth and a lower magnetic pole tooth is disposed on both sides of a moving element so as to surround the moving element. However, similar effects can be obtained in the case where the magnetic material is disposed on one side. 
         [0148]    Although a holding method of a positional relation between a permanent magnet, a permanent magnet holding member, and an armature is not described in the embodiments of the present invention, a support structure similar to a conventional linear motor (for example, a linear guide, a guide roller, and a cam follower) can be used. 
         [0149]    The present invention is not limited to the above-described embodiments and includes various variations. For example, the above-described embodiments describe the present invention in detail for clarification, and every configurations described above may not be necessarily included. Further, a configuration of each embodiment can be partially replaced to configurations of the other embodiments. Furthermore, a configuration of each embodiment can be added to configurations of the other embodiments. Further, a part of a configuration of each embodiment can be added to, deleted from, and replaced from other configurations. 
         [0150]    &lt;Other Idea Disclosed in Present Invention&gt; 
         [0151]    The present invention includes technical ideas described below. 
         [0152]    &lt;&lt;Appendix 1&gt;&gt; 
         [0153]    A linear motor, including: 
         [0154]    an armature including a first magnetic pole tooth pair and a second magnetic pole tooth pair which are two magnetic pole teeth disposed opposite to each other via a space in a vertical direction and the armature in which the first and second magnetic pole tooth pairs are arranged in a longitudinal direction; and 
         [0155]    an moving element which relatively moves in a longitudinal direction with respect to the armature, 
         [0156]    wherein each of the magnetic pole teeth of the first and second magnetic pole tooth pairs is connected by a magnetic material, 
         [0157]    a first winding wound around the magnetic pole teeth of either or both of the first magnetic pole tooth pair and a second winding wound around the magnetic pole teeth of either or both of the second magnetic pole tooth pair are included, and 
         [0158]    the magnetic material includes an electric resistance unit having a larger electric resistance value than an electric resistance value of the magnetic material along a longitudinal direction. 
         [0159]    According to appendix 1, a linear motor can be provided which can effectively use a magnetic flux between magnetic poles adjacent in a longitudinal direction and can reduce a loss of the magnetic flux. Further, a small-scale linear motor can be provided. 
         [0160]    &lt;&lt;Appendix 2&gt;&gt; 
         [0161]    The linear motor according to appendix 1, wherein directions of magnetic fluxes supplied from the first and second windings are opposite each other, and the electric resistance unit is radially provided. 
         [0162]    According to appendix 2, a linear motor in which a loss is reduced can be provided. Further, a linear motor which realizes single-phase driving or three-phase driving by three armatures is especially suitable. 
         [0163]    &lt;&lt;Appendix 3&gt;&gt; 
         [0164]    The linear motor according to appendix 1, wherein the armature includes a third magnetic pole tooth pair including two magnetic pole teeth disposed opposite to each other via a space in a vertical direction, 
         [0165]    the third magnetic pole tooth pair is connected to the magnetic material and arranged in a longitudinal direction with respect to the first and second magnetic pole tooth pairs, 
         [0166]    the third magnetic pole tooth pair includes a third winding wound around either or both of the magnetic pole teeth, 
         [0167]    one of the first, second, and third windings supplies a magnetic flux opposed to at least one of two other windings, and 
         [0168]    the electric resistance unit is radially provided. 
         [0169]    According to appendix 3, a linear motor in which a loss is reduced can be provided. In addition, a linear motor which realizes three-phase driving by one armature is especially suitable. 
         [0170]    &lt;&lt;Appendix 4&gt;&gt; 
         [0171]    The linear motor according any one of appendixes 1 to 3, wherein the electric resistance unit is a slit provided with a predetermined depth to the magnetic material along a longitudinal direction, and a cooling pipe is provided to the slit. 
         [0172]    According to appendix 4, while realizing downsizing a linear motor, cooling performance can be improved. 
         [0173]    &lt;&lt;Appendix 5&gt;&gt; 
         [0174]    The linear motor according to appendix 4, wherein the slit has a depth to reach the inside of the volume surrounded by the first winding or the second winding wound around magnetic pole teeth. 
         [0175]    According to appendix 5, cooling performance of the winding can be improved. 
         [0176]    &lt;&lt;Appendix 6&gt;&gt; 
         [0177]    The linear motor according to appendix 4 or 5, wherein the cooling pipe comes into contact with the winding. 
         [0178]    According to appendix 6, cooling performance of the winding can be improved. 
         [0179]    &lt;&lt;Appendix 7&gt;&gt; 
         [0180]    The linear motor according to any one of appendixes 1 to 6, a communication hole for communicating the winding with the outside of the magnetic material. 
         [0181]    According to appendix 7, cooling performance of the winding can be improved. 
         [0182]    &lt;&lt;Appendix 8&gt;&gt; 
         [0183]    An apparatus mounting the linear motor according to any one of appendixes 1 to 7. 
         [0184]    According to appendix 8, an apparatus can be provided which includes a linear motor according to any one of appendixes 1 to 7 and obtains effects on the linear motor. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           2   a,    2   b,    2   c,    2   d,    2   e,    2   f,    2   g,    2   h  winding 
           5 ,  5   a,    5   b  permanent magnet 
           7   e   1 ,  7   e   2  iron core 
           11 ,  11   a,    11   b,    11   c,    11   a   1 ,  11   a   2 ,  11   a   3  upper magnetic pole tooth 
           12 ,  12   a,    12   b,    12   c,    12   a   1 ,  12   a   2 ,  12   a   3  lower magnetic pole tooth 
           13 ,  13   a,    13   b,    13   c  magnetic material 
           20  cooling pipe 
           33  slit (electric resistance unit) 
           40  winding depth 
           41  slit depth 
           45  connecting portion 
           51  magnetization direction of permanent magnet 
           52  permanent magnet holding member 
           53  base plate 
           55  moving element 
           56  connecting plate 
           57  fixing hole 
           58  iron core connecting portion 
           61   a,    61   b,    61   c,    61   d  magnetic flux 
           70   a,    70   b,    70   c  magnetic path width 
           71 ,  72  magnetic flux 
           81 ,  81   a,    81   b  communication hole 
           85  moving member supporting tool 
           91  driving apparatus 
           100 ,  101 ,  102  armature 
           200 ,  201  linear motor 
           350  hermetic compressor 
           360  refrigerator 
           361  refrigerator body 
           362  refrigeration chamber 
           363  upper freezing chamber 
           364  lower freezing chamber 
           365  vegetable chamber 
           366  cooler 
           367  machine chamber 
           380  heat exchanger 
           381  water heater heat exchanger 
           382  fan 
           385  heat pump unit 
           386  outdoor unit 
           390  show case 
           391  condensing unit 
           392  product shelf 
           393  evaporator 
           394  fan 
           395  cooling air duct 
           396  heat exchanger 
           397  fan 
           398  electric component box 
           399  accumulator 
           400  railway vehicle 
           401  indoor side heat exchanger 
           402  indoor side fan 
           403  outdoor side heat exchanger 
           404  outdoor side fan 
           405  vehicle air conditioner 
           410  automobile 
           411  heat exchanger