JP4078870B2 - Moving coil linear motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a moving coil linear motor, and more particularly to a moving coil linear motor that includes a stator having a permanent magnet and a mover having an armature coil and is used for transporting a curtain or the like.
[0002]
[Prior art]
A movable coil type linear motor that uses a permanent magnet as the field on the stator side and an iron core or yoke on the armature coil to efficiently use the magnetic flux generated by this field is widely used for conveying curtains and the like. in use. In such a moving coil linear motor, it is very difficult to obtain a magnetic balance in a direction perpendicular to the moving direction of the mover relative to the stator.
[0003]
Normally, a guide mechanism is required that regulates the position of the mover relative to the stator in the direction perpendicular to the moving direction while ensuring the smooth advance of the mover with respect to the longitudinal direction of the stator. This guide mechanism is also necessary for receiving gravity applied to the mover when the moving direction of the mover is not the vertical direction.
[0004]
FIG. 9 is a cross-sectional view showing a structural example of a conventional moving coil linear motor. A linear motor stator 4 having a permanent magnet 41 and a linear motor movable element 3 having an armature coil 32 are arranged in an internal space of the stator rail 1 made by extrusion molding of aluminum or the like. The armature coil 32 is obtained by winding a copper wire around a resin coil bobbin 31 and is fixed to a resin guide member 35.
[0005]
The left and right ends of the guide member 35 engage with guide protrusions 1b formed on the inner surface of the stator rail 1, and are slidable in the longitudinal direction (direction perpendicular to the paper surface) of the stator rail 1, Movement is restricted in the vertical direction (vertical direction and horizontal direction). By such a guide mechanism, the linear motor movable element 3 including the armature coil 32 can smoothly travel in the longitudinal direction of the stator rail 1 (the linear motor stator 4 fixed to the stator rail 1). The position with respect to the near motor stator 4 in the vertical direction is restricted.
[0006]
[Problems to be solved by the invention]
As described above, the guide member 35 of the linear motor movable element 3 is made of a resin material having a small frictional force in order to ensure smooth sliding performance with the guide protrusion 1 b of the stator rail 1. Further, the coil bobbin 31 is made of a resin molded product in order to ensure insulation performance between the wound copper wire and the iron core disposed inside thereof. Conventionally, these two members have been made, managed, and assembled as individual members, so that the number of parts is increased, and there is room for improvement from the viewpoint of reducing management costs and assembly costs.
[0007]
The present invention has been made in view of the above problems, and its object is to provide a rational structure capable of reducing the number of parts of a conventional moving coil linear motor and reducing the cost. Is to provide.
[0008]
[Means for Solving the Problems]
A moving coil linear motor according to the present invention includes a stator rail to which a stator having a permanent magnet for field is fixed, a mover having an armature coil wound around a coil bobbin, and the length of the stator rail. A guide mechanism that ensures smooth movement of the mover relative to the stator rail in a direction and restricts the position of the mover relative to the stator rail in a direction perpendicular to the longitudinal direction of the stator rail, A movable coil type linear motor in which the mover moves along the longitudinal direction of the stator rail by electromagnetic force acting between the armature coil and the permanent magnet, wherein the guide mechanism includes the armature coil A sliding portion projecting from a flange portion of the coil bobbin in a direction perpendicular to the longitudinal direction of the stator rail, and a guide projection provided on the stator rail Consists, together with the guide protrusion slidably held along the sliding portion in the longitudinal direction of the stator rail, to regulate the position in the direction perpendicular to the sliding direction, the movable element is the fixed A plurality of armature coils arranged at a predetermined pitch in the longitudinal direction of the slave rail, and the sliding portions are provided at a ratio of one to a predetermined number of coil bobbins of the plurality of armature coils, The sliding part is formed in a direction perpendicular to the axial direction from the flange part of the coil bobbin and on both sides, and the fixed angle of the coil bobbin with respect to the mover yoke holding the plurality of armature coils at a predetermined pitch is set to a predetermined number. By changing 90 degrees at a rate of one, the sliding portion of the coil bobbin is configured to engage with the guide protrusion at a rate of one per predetermined number.
[0009]
According to such a configuration, the number of parts and the number of assembling steps can be reduced as compared with the conventional configuration in which the coil bobbin and the sliding member are separate members, so that the cost of the movable coil linear motor can be reduced. Further, it is possible to suppress an increase in contact area (and consequently sliding resistance) between the plurality of sliding portions and the guide projections of the stator rail. Alternatively, it is possible to suppress an increase in sliding resistance between the sliding portion and the guide protrusion due to the dimensional variation of the plurality of sliding portions. Furthermore, since it is not necessary to prepare two types of coil bobbins (with and without sliding portions), it is advantageous in terms of resin molding die costs and component management costs.
[0010]
In a preferred embodiment, the coil bobbin and the sliding portion are integrally formed by resin molding. Thereby, the further cost reduction of a movable coil type linear motor is attained.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a cross-sectional view showing an entire linear motor according to a reference embodiment. The linear motor includes a stator rail 1, a linear motor movable element 3, a linear motor stator 4, and a rectifying substrate 5 disposed in the internal space of the stator rail 1.
[0017]
The stator rail 1 has a substantially C-shaped cross section and is formed by extrusion molding of aluminum or the like. A magnet holding projection 1a for holding the linear motor stator 4, a guide projection 1b for slidably guiding the linear motor mover 3, and a substrate holding projection 1c for holding the rectifying substrate 5 are formed on the inner surface. Yes. The linear motor stator 4 includes a permanent magnet 41 and a stator yoke 42 that constitute a magnetic circuit. The linear motor movable element 3 includes an armature coil 32, its iron core 33, and a movable element yoke 34. The rectifying substrate 5 is in electrical contact with the brush 6 connected to the armature coil 32 and has a function of supplying a drive voltage output from the controller to the armature coil 32.
[0018]
FIG. 2 is a block diagram of the controller. The controller 2 includes a rectifying / smoothing unit 2a, a voltage adjusting unit 2b, and a positive / negative inversion unit 2c. The input side of the controller 2 (input terminal of the rectifying / smoothing unit 2a) is connected to a commercial power supply (AC voltage), and the output side (output terminal of the positive / negative reversing unit 2c) is connected to the armature coil 32 via the rectifying substrate 5 and the brush. It is connected.
[0019]
The rectifying / smoothing unit 2a converts a commercial power supply (AC voltage) into a DC voltage. The voltage adjusting unit 2b includes a switching element such as an FET and a gate control circuit thereof, and generates an adjusted output voltage to the linear motor from the DC voltage obtained by the rectifying / smoothing unit 2a. The positive / negative reversing unit 2c is configured by a relay. With such a configuration, the controller 2 generates positive and negative drive voltages necessary for driving the linear motor movable element 3 at a predetermined speed from the commercial power source, and drives the armature coil 32 via the rectifying substrate 5 and the brush. Supply voltage.
[0020]
FIG. 3 is a perspective view showing the structure of the linear motor movable element 3. The linear motor movable element 3 includes an armature coil 32, its iron core 33, and a movable element yoke 34. The armature coil 32 is obtained by winding a copper wire in a substantially cylindrical shape around a coil bobbin 31 that is a resin molded product. The iron core 33 and the mover yoke 34 form a magnetic circuit through which the magnetic flux generated by the armature coil 32 passes. Thereby, the electromagnetic force which acts between the permanent magnet 41 which is a field magnet and the armature coil 32 is strengthened.
[0021]
The mover yoke 34 also has a function of mechanically holding the plurality of iron cores 33 at predetermined intervals. The iron core 33 is fixed to the mover yoke 34 by caulking, for example, and one armature coil 32 is arranged around each iron core 33. Spacing between adjacent armature coils in this preferred embodiment is configured such that 2P / 3 the pole pitch P of the permanent magnets 41 of the linear motor stators 4 (see FIG. 5), which enables the three-phase linear motor Is configured.
[0022]
One end side of each armature coil 32 is electrically connected to an individual brush 6 fixed to the brush base 61, and the other end side is commonly connected. The positive and negative drive voltages output from the controller 2 are supplied to the armature coil 32 via the rectifying substrate 5 and the brush 6. The linear motor operates by an electromagnetic force acting between the current flowing through the armature coil 32 and the magnetic flux generated by the permanent magnet 41. That is, the linear motor movable element 3 to which the armature coil 32 is fixed moves linearly with respect to the linear motor stator 4 to which the permanent magnet 41 is fixed. In addition, you may employ | adopt the structure of not only the above-mentioned three-phase linear motor but the structure of a multiphase linear motor of two phases or four phases or more.
[0023]
FIG. 4 is a perspective view of the coil bobbin 31 constituting the armature coil 32. The coil bobbin 31 has a cylindrical portion 31b around which a copper wire is wound and an iron core is inserted to insulate the two, and a pair of flange portions 31a that hold the wound copper wire located at both ends thereof. Further, a pair of sliding portions 31c protrudes from both flange portions 31a on both sides at right angles to the axial direction. As can be seen from FIGS. 1 and 3, the pair of sliding portions 31 c engage with a pair of guide protrusions 1 b formed on the inner surface of the stator rail 1 and slide in the longitudinal direction of the stator rail 1. It is free to move.
[0024]
FIG. 5 is a perspective view showing the structure of the linear motor stator 4. The linear motor stator 4 includes a plurality of permanent magnets 41 as field magnets arranged in a line in the longitudinal direction of an elongated plate-like stator yoke 42. As can be seen from FIG. 1, the linear motor stator 4 is fixed to the stator rail so that both ends of the stator yoke 42 in the width direction engage with a pair of magnet holding protrusions 1a formed on the inner surface of the stator rail 1. 1 is disposed in the upper part of the internal space.
[0025]
A stator yoke 42 of the linear motor stator 4 is provided over substantially the entire length of the stator rail 1, and a plurality of permanent magnets 41 are arranged in a line over the substantially entire length of the stator yoke 42. The plurality of permanent magnets 41 are fixed to the stator yoke 42 so that N poles and S poles are alternately arranged on the front side. The stator yoke 42 and the plurality of permanent magnets 41 are fixed by a magnetic attractive force that interacts with each other, but may be fixed together with an adhesive or the like. The magnetic pole pitch of the adjacent permanent magnets 41 is indicated by P in FIG.
[0026]
The surface (lower surface) on the front side (opposite side of the stator yoke 42) of the permanent magnet 41 faces the upper surface of the iron core 33 of the linear motor movable element 3 with a predetermined gap as shown in FIG. A magnetic attractive force acts between the permanent magnet 41 and the iron core 33. However, the linear motor stator 4 including the permanent magnet 41 is fixed by the magnet holding projection 1a of the stator rail 1, and the linear motor movable element 3 including the iron core 33 is guided by the sliding portion 31c of the coil bobbin 31 and the stator rail 1. The vertical movement is regulated by the engagement with the protrusion 1b. Therefore, the gap between the permanent magnet 41 and the iron core 33 (between the linear motor stator 4 and the linear motor movable element 3) is kept constant, and a linear motor having good thrust characteristics is configured.
[0027]
FIG. 6 is a diagram showing a conductive pattern of the rectifying substrate 5. The rectifying substrate 5 is an elongated printed wiring board 51 that extends over substantially the entire length of the stator rail 1, and is fixed to the substrate holding protrusion 1 c of the stator rail 1. A pair of conductive (copper foil) patterns 52 and 53 extending in the longitudinal direction as shown in FIG. 6 are formed on the surface of the rectifying substrate 5 in contact with the brush 6 by etching or the like.
[0028]
Each of the copper foil patterns 52 and 53 is formed with brush contact portions 52 a and 53 a arranged at a predetermined pitch at a substantially central portion in the height direction of the rectifying substrate 5. That is, the brush contact portions 52a formed on the upper copper foil pattern 52 and the brush contact portions 53a formed on the lower copper foil pattern 53 are alternately arranged at a predetermined pitch P in the longitudinal direction. This pitch P is the same as the magnetic pole pitch P of the permanent magnet 41 described above.
[0029]
The pair of copper foil patterns 52 and 53 are connected to positive and negative drive voltages output from the controller 2. For example, the upper copper foil pattern 52 is connected to a positive drive voltage, and the lower copper foil pattern 53 is connected to a negative drive voltage. Connections opposite to each other may be used.
[0030]
As described above, the brush 6 electrically connected to one end side of each armature coil 32 is fixed to the brush base 61 of the linear motor movable element 3, and the pitch (adjacent brush interval) is 2P / 3. When the linear motor movable element 3 moves in the longitudinal direction of the stator rail 1, the brush 6 moves while being in slidable contact with a substantially central portion of the rectifying substrate 5 in the height direction. Therefore, as the linear motor movable element 3 moves (advances), the brush 6 alternately contacts the brush contact portions 52 a and 53 a arranged in the longitudinal direction of the rectifying substrate 5. Thus, positive and negative drive voltages (currents) are alternately supplied to the respective armature coils 32 via the rectifying substrate 5 and the brush 6.
[0031]
Note that the method of alternately supplying positive and negative drive voltages to each armature coil 32 is not limited to the method using the rectifying substrate 5 and the brush 6, and other methods may be used. For example, there is a method of configuring a brushless motor using a curl cord.
[0032]
As described above, the present according to the reference embodiment of the arrangement, integrally with the flange portion 31a of the sliding portion 31c is the coil bobbin 31 of the linear motor movable element 3 to engage freely in the guide protrusion 1b and sliding the stator rail 1 Since the coil bobbin and the sliding member are separate members, the number of parts and the number of assembling steps are reduced, and the cost of the movable coil linear motor can be reduced.
[0033]
FIG. 7 is a perspective view of a linear motor movable element 3 constituting a linear motor according to another reference embodiment. In addition, about the other part containing the linear motor stator 4 and the rectification | straightening board | substrate 5, it is the same structure as said reference form, and illustration and description are abbreviate | omitted.
[0034]
In the above reference embodiment, the linear motor movable element 3 constitutes a three-phase, one-pole motor, but a larger propulsive force (driving force) may be required depending on the form of the load. In that case, it is necessary to enlarge the cross-sectional shape (FIG. 1) of the linear motor. Alternatively, it is necessary to increase the number of armature coils 32 arranged in the traveling direction of the linear motor movable element 3.
[0035]
This reference form provides a structure suitable for increasing the number of armature coils 32. A plurality of sliding parts 31c are not provided on all coil bobbins 31 as in the above reference form. One coil bobbin 31 is provided with one sliding portion 31c. In the example of FIG. 7, a sliding portion 31c is provided at a rate of one for every four coil bobbins 31, that is, every three coil bobbins 31, and a three-phase three-pole motor is configured.
[0036]
By doing so, it is possible to suppress an increase in the contact area (and consequently the sliding resistance) between the plurality of sliding portions 31c and the guide protrusion 1b of the stator rail 1. Or the increase in the sliding resistance of the sliding part 31c and the guide protrusion 1b resulting from the dimensional dispersion | variation of the some sliding part 31c can be suppressed.
[0037]
In this reference embodiment, the guide protrusions 1b are provided on a quarter of the number of coil bobbins 31, and the guide protrusions 1b are not provided on the other coil bobbins 31 ′. That is, two types of coil bobbins 31 and 31 ′ are prepared. Of course, as in the above reference embodiment, it is possible to prepare only one type of coil bobbin 31 on which the guide protrusion 1b is formed and use it as another coil bobbin 31 'by cutting away the unnecessary guide protrusion 1b. .
[0038]
FIG. 8 is a perspective view of the linear motor movable element 3 constituting the linear motor according to the embodiment of the present invention . Also in this embodiment, other parts including the linear motor stator 4 and the rectifying substrate 5 have the same configuration as the above-described reference embodiment, and illustration and description thereof are omitted.
[0039]
As described above, the reference form requires two types of coil bobbins 31 and 31 ′. Alternatively, it is necessary to cut off unnecessary guide protrusions 1b in order to make another coil bobbin 31 'from one type of coil bobbin 31 on which the guide protrusions 1b are formed.
[0040]
In the present embodiment, only one type of coil bobbin 31 on which the guide protrusion 1b is formed is prepared, and for the coil bobbin 31 that does not have a guide function, the orientation of the coil bobbin 31 with respect to the mover yoke 34 is 90 as shown in FIG. It is rotated and fixed. By doing so, it is not necessary to prepare two types of coil bobbins, which is advantageous in terms of resin molding die costs and component management costs.
[0041]
In this embodiment, a nine-phase three-pole motor is configured using nine armature coils 32, but the present invention is not limited to this. Further, the ratio and arrangement of the coil bobbin having the guide function and the coil bobbin not having the guide function are not limited to the examples shown in FIGS. What is necessary is just to set suitably in consideration of the form etc. of load.
[0042]
As described above, in the present embodiment, the coil bobbin and the mover guide piece are integrated as in the first embodiment, so that the number of parts can be reduced and the cost can be reduced, and the coil bobbin can be selectively disposed. Because the contact area between the stator guide and the mover guide piece can be adjusted by this, a moving coil type linear motor that does not increase sliding frictional resistance even when the mover is lengthened due to the large thrust required from the load configuration it can.
[0043]
【The invention's effect】
As described above, according to the movable coil linear motor of the present invention, the sliding portion of the linear motor movable element that is slidably engaged with the guide protrusion of the stator rail is formed integrally with the flange portion of the coil bobbin. Therefore, the number of parts and the number of assembling steps are reduced as compared with the conventional configuration in which the coil bobbin and the sliding member are separate members, and the cost of the movable coil linear motor can be reduced.
[0044]
In addition, by providing a sliding portion at a ratio of a predetermined number of coil bobbins of a plurality of armature coils, an increase in sliding resistance between the plurality of sliding portions and the guide projections of the stator rail is suppressed. Smooth movement of the mover relative to the stator is ensured.
[0045]
Further, by changing the fixed angle of the coil bobbin with respect to the mover yoke by 90 degrees at a ratio of one to a predetermined number, only one type of coil bobbin can be slid at a ratio of one to a predetermined number without preparing two types of coil bobbins. Since it can comprise so that a moving part may engage with a guide protrusion, it becomes advantageous at the surface of the metal mold | die cost of resin molding, and the management cost of components.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an entire linear motor according to a reference embodiment.
FIG. 2 is a block diagram of a controller.
FIG. 3 is a perspective view showing a structure of a linear motor movable element.
FIG. 4 is a perspective view of a coil bobbin constituting an armature coil.
FIG. 5 is a perspective view showing a structure of a linear motor stator.
FIG. 6 is a diagram showing a conductive pattern of a rectifying substrate.
FIG. 7 is a perspective view of a linear motor movable element constituting a linear motor according to a reference embodiment.
FIG. 8 is a perspective view of a linear motor movable element constituting the linear motor according to the embodiment of the present invention .
FIG. 9 is a cross-sectional view showing a structural example of a conventional moving coil linear motor.

Claims (2)

A stator rail to which a stator having a permanent magnet for field is fixed, a mover having an armature coil wound around a coil bobbin, and the stator rail of the mover in the longitudinal direction of the stator rail And a guide mechanism for restricting the position of the mover relative to the stator rail in a direction perpendicular to the longitudinal direction of the stator rail, and ensuring a smooth movement with respect to the stator rail, between the armature coil and the permanent magnet A movable coil type linear motor in which the mover moves along the longitudinal direction of the stator rail by an electromagnetic force acting on the stator rail, wherein the guide mechanism extends from a flange portion of a coil bobbin of the armature coil to the stator rail And a guide projection provided on the stator rail, the guide projection serving as the sliding portion. Thereby slidably held along the longitudinal direction of the serial stator rails, to regulate the position in the direction perpendicular to the sliding direction, the mover is disposed at a predetermined pitch in a longitudinal direction of the stator rail A plurality of armature coils, the sliding portions being provided at a ratio of one to a predetermined number of the coil bobbins of the plurality of armature coils, and hanging in the axial direction from the flange portions of the coil bobbins.
The sliding part is formed in a straight direction and on both sides, and the fixed angle of the coil bobbin with respect to the mover yoke holding the plurality of armature coils at a predetermined pitch is changed by 90 degrees at a ratio of one to a predetermined number. Accordingly , the movable coil linear motor is configured such that the sliding portion of the coil bobbin is engaged with the guide projection at a ratio of one to a predetermined number .   The movable coil linear motor according to claim 1, wherein the coil bobbin and the sliding portion are integrally formed by resin molding.

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