JPH0697832B2 - Linear pulse motor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a permanent magnet type linear pulse motor that is widely used as a linear drive stepping motor in the field of OA equipment, industrial machinery and the like.

[Conventional technology]

As is well known, the linear pulse motor described above moves a slider on which a work is mounted along a scale in response to an input pulse signal, and has recently been widely used for driving a printer head, driving an XY table, and the like. It is used for various purposes.

Next, the basic structure of a conventional permanent magnet type linear pulse motor and its operating principle will be described with reference to FIGS. 6 and 7. First, in FIG. 6, 1 is a slider for mounting the work 2, 3 is a wheel of the slider 1, 4 is a linear scale laid along the moving path of the slider 1, and the slider 1 is a linear pulse motor described below. By the driving operation of, the step 4 moves in the direction of arrow P on the scale 4. Here, the linear pulse motor has two sets of cores 5 and 6 each having a pair of magnetic pole teeth, and the magnetic pole teeth are juxtaposed above the scale toward the tooth row 4a of the scale 4 and each of the cores 5 and 6. Permanent magnets 7 and 8 coupled to the back surface, and a yoke 9 extending between the permanent magnets 7 and 8,
It is composed of an exciting coil 10 wound around the magnetic pole teeth 5a, 6a of the cores 5, 6. Excitation coil 1 is attached to each core 5 and 6.
0 is connected in series to each pair of magnetic pole teeth with the winding direction being opposite.

The step drive operation with such a configuration is shown in FIGS.
As shown in. That is, the magnetic pole teeth of the core coupled with the permanent magnets and the pitches of the scale tooth rows are arranged in a relationship as shown in the drawing, and are shown corresponding to the respective modes (a) to (d). By sequentially switching the input pulse signal i applied to each exciting coil 10 from the controller which does not exist, the magnetic flux φm supplied from the permanent magnet and the magnetic flux φi generated in the exciting coil are adjusted for each magnetic pole tooth, and each core is adjusted. The magnetic flux between the magnetic pole teeth and the scale of the
It is well known that the magnetically stable positions of the magnetic pole teeth and the scale-side tooth row are sequentially changed by this and the stepwise motion is performed.

[Problems to be Solved by the Invention]

By the way, in the above-mentioned conventional linear pulse motor, the core facing the upper part of the scale is arranged vertically, the permanent magnets, the yokes, etc. are stacked on the core, and the exciting coil has the height of the magnetic pole teeth of each core. A linear pulse motor is assembled and configured by winding in a direction. For this reason, the height H of the linear pulse motor as a whole becomes large, and it becomes difficult to apply it to a device in which the height of the entire work including the workpiece mounted on the slider is limited in view of the installation space.

The present invention has been made in view of the above points, and an object thereof is to change a structure of a linear pulse motor from a conventional method to drastically reduce the height dimension thereof and to provide a device subject to dimension restriction in the height direction. It is to provide a thin linear pulse motor that can be applied to.

[Means for Solving the Problems]

In order to achieve the above object, in the linear pulse motor of the present invention, a pair of scales are laid on the left and right sides of the slider with the tooth rows facing inward, and a pair of scales are provided on both the left and right sides of the slider so as to face each scale. U-shaped core having two pairs of drive elements, each of which has a pair of magnetic pole teeth facing the tooth row of the scale, an exciting coil wound around the core, and The permanent magnet has a magnetic pole surface superposed on the side surfaces of the magnetic pole teeth and coupled to the core, and a yoke having a magnetic pole surface superposed on the magnetic pole surface on the back side of the permanent magnet and having a tip protruding toward the side surface of the scale.

[Action]

With the above structure, a closed magnetic path is formed between the scale and the scale for each set of driver elements disposed on the left and right sides of the slider, and returns to the permanent magnet from the permanent magnet through the magnetic pole teeth of the core, the scale, and the yoke. By applying an input pulse signal to the exciting coil, the magnetic flux between each magnetic pole tooth and the scale changes. Therefore, the slider is stepwise driven along the scale by switching and controlling the input pulse signal applied to the exciting coil and its direction between the left and right drivers in a designated mode.

Moreover, by arranging all parts of the driver and the scale that compose the linear pulse motor for the slider on both the left and right sides of the slider, the overall height dimension is greatly reduced compared to the conventional configuration described above. it can. The linear pulse motor is required to move the slider by supporting the slider separately from the scale of the linear pulse motor on a support guide installed separately and supporting the full load weight including the work with this support guide. Only the propulsive force is applied, and even if the load weight is large, the linear pulse motor is not unduly loaded.

〔Example〕

1 to 5 show the structure of an embodiment of the present invention, and the same members corresponding to FIG. 6 are designated by the same reference numerals. First, the slider 1 on which the work 2 is mounted is formed as a flat base plate, and the slider 1 is guided and supported by two left and right support guide bars 11 penetrating the base plate.

On the other hand, on the left and right sides of the slider 1, a pair of scales 4 are laid parallel to the support guide rods 11 with the tooth row 4a facing inward. It is equipped with two sets of drive elements, shown at 12. Here, the pitch of the tooth row 4a is laid between the pair of scales 4 by a relative shift of 1/2 pitch. The driver 12 is a U-shaped core 13 having a pair of magnetic pole teeth 13a and 13b facing the tooth row 4a of the scale 4, an exciting coil 14 wound around the center of the core 13, and a pair of magnetic poles. Teeth 13a, 13b
A strip-shaped permanent magnet 15 that is connected to the upper and lower side surfaces of the core 13 with the tip portion of the core 13 sandwiched between the permanent magnet 15 and the permanent magnet 15;
It is constructed as an assembly with two upper and lower yokes 16 which are superposed on the back surface side of the above so that the tip thereof projects toward the side surface of the scale 4. The permanent magnet 15 is magnetized in the thickness direction as shown in FIG. 3, and one pole face (N pole) of the pole teeth 13a, 13b is connected to the yoke 16a.
Are arranged so that the other magnetic pole surface (S pole) faces each other.

Next, the magnetic operation of the driver element 12 having the above-described structure will be described with reference to FIGS. 4 and 5. First, the magnetic pole teeth 13a and 1b of the core 13 are connected to the scale 4 from the N pole of the permanent magnet 15 between them. Teeth 13a, 13b,
Each independent closed magnetic path that returns to the S pole of the permanent magnet 15 via the scale 4 and the yoke 16 is formed. Here, the magnetic flux supplied from the permanent magnet 15 is shown by φm (dotted line). On the other hand, apart from the closed magnetic path described above, a closed magnetic path including an exciting coil 14 is formed between the U-shaped core 13 and the scale 4 so as to partially overlap the magnetic path on the permanent magnet side. There is. The magnetic fluxes generated in the positive and negative directions of the input pulse signal i applied to the exciting coil 14 are represented by arrows + φi and -φi, respectively.

Therefore, when the pulse signal is not input to the exciting coil 14, the magnetic flux φm by the permanent magnet 15 is supplied between the magnetic pole teeth 13a and 13b and the scale 4. On the other hand, when a positive pulse signal i is applied to the exciting coil 14, the magnetic flux φm is superposed with the magnetic flux + φi generated in the exciting coil 14, whereby a magnetic flux φm is generated for one magnetic pole tooth 13a. + Φi is added in the same direction, and the other magnetic pole tooth 13b
, The magnetic fluxes φm and + φi cancel each other out. On the other hand, when the pulse signal i applied to the exciting coil 14 is switched in the negative direction, contrary to the above, the magnetic flux φm and −φi cancel each other at the magnetic pole tooth 13a and the magnetic flux φ at the magnetic pole tooth 13b.
Then, m and −φi are added.

Therefore, as shown in FIG. 1, the input pulse signal applied to the exciting coil 14 and the direction of the input pulse signal between the two sets of the driver elements 12 arranged on the left and right of the slider 1 are sequentially switched in a designated mode. Row 4a and driver 12 of each set
The magnetically stable position between the two changes like the conventional permanent magnet type linear pulse motor shown in FIGS. 7 (a) to 7 (d), which causes the slider 1 to step along the scale 4. become. In this case, the total load weight of the slider 1 including the work 2 is the support guide rod 11 shown in FIG.
Being carried by the linear pulse motor, the linear pulse motor need only provide the propulsive force necessary to move the slider along the guide support rod 11.

Moreover, according to the above configuration, the scale 4 and the driver 12
Are all arranged on both the left and right sides of the slider 1, the overall height dimension h (see FIG. 2) is greatly reduced compared to the height dimension H of the conventional structure shown in FIG. .

In the illustrated embodiment, the permanent magnets and the yokes are arranged on the upper and lower sides of the magnetic pole teeth of the core for each set of the driving elements, but the permanent magnets and the yokes are arranged on only one side. It is also possible to carry out. In the illustrated example, the tooth row pitch is shifted by 1/2 pitch between the left and right scales 4, but the tooth row pitches of the scale 4 are made uniform, and instead, between the two left and right sets of the driver elements 12 is replaced. The mounting position may be shifted by an amount corresponding to 1/2 pitch of the scale tooth row.

〔The invention's effect〕

As described above, in the linear pulse motor of the present invention, a pair of scales are laid on the left and right sides of the slider with the tooth row facing inward, and two sets are mounted on the left and right sides of the slider so as to face each scale. The U-shaped core having a pair of magnetic pole teeth facing the tooth row of the scale, the exciting coil wound around the core, and one magnetic pole surface. The permanent magnet is overlapped with the side surface of the magnetic pole tooth and coupled to the core, and the yoke is overlapped with the magnetic pole surface on the back side of the permanent magnet and has a tip protruding toward the side surface of the scale. It is possible to drive the slider step by step along the scale by switching the input pulse signal applied to the excitation coils of the driver elements arranged on both the left and right sides of the Hakare height dimension reduction of the concrete surface, it is possible to provide a linear pulse motor favorable thin particularly applicable to a device that is restricted in the height direction.

[Brief description of drawings]

FIG. 1 is a plan view showing the structure of an embodiment of the present invention, FIG. 2 is a front view of FIG. 1, FIG. 3 is a perspective view of the structure of a driver element in FIG. 1, and FIGS. FIG. 6 is an explanatory view of the magnetic operation of the driver, FIG. 6 is a configuration diagram of a conventional linear pulse motor, and FIGS. 7A to 7D are operation explanatory views of FIG. In each figure, 1: slider, 2: workpiece, 4: scale, 4a: tooth row, 12: driver, 13: core, 13a, 13b: magnetic pole teeth, 14: exciting coil, 15: permanent magnet, 16: yoke , Φm: magnetic flux supplied from the permanent magnet, + φi, −φi: magnetic flux generated by the exciting coil.

Claims (1)

[Claims] 1. A linear pulse motor for stepwise driving a slider on which a work is mounted along an scale by an input pulse signal, and a pair of scales laid on both left and right sides of the slider with tooth rows facing inward. A U-shaped core having two sets of driver elements provided on both left and right sides of the slider so as to face each scale, each driver element having a pair of magnetic pole teeth facing a tooth row of the scale; An exciting coil wound around the core, a permanent magnet having one magnetic pole surface superposed on a side surface of the magnetic pole tooth and coupled to the core, and a permanent magnet superposed on a rear side magnetic pole surface of the permanent magnet, and a tip thereof on a side surface of the scale. A linear pulse motor comprising a yoke projecting toward.