JPH01214253A - Linear pulse motor - Google Patents

Abstract

PURPOSE:To reduce dimensions in the vertical direction by forming an apparatus into a structure equipped with drivers on both left and right sides of a slider. CONSTITUTION:A slider 1 is guide-supported by a supporting guide bar 11, and a pair of scales 4 with dentitions 4a facing inward are provided in parallel with said supporting guide bar 11 on both left and right sides of said slider 1. In opposition to said scales 4, two sets of drivers 12 are provided in both left and right side parts of the slider 1. Between said pair of scales 4, said dentitions 4a are laid through deviation of their pitch relatively by 1/2 pitch. Said driver 12 is composed of a U-shaped core 13, an exciting coil 14, a permanent magnet 15, and a yoke 16. Said slider 1 can be driven via said driver 12 by an exciting pulse given to said exciting coil 14.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is applicable to OA as a linear drive stepping motor.
This article relates to permanent magnet linear pulse motors that are widely used in the fields of equipment and industrial machinery.

[Conventional technology]

As is well known, the linear pulse motor mentioned above moves a slider on which a work is mounted stepwise along a scale using an input pulse signal, and has recently been used in a wide range of applications such as driving printer heads and driving X-Y tables. Used for this purpose.

Next, the basic structure and operating principle of a conventional permanent magnet type linear pulse motor will be explained with reference to FIGS. 6 and 7. First, in Fig. 6, 1 is the slider on which the workpiece 2 is mounted, 3 is the 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. The driving operation causes stepwise movement on the scale 4 in the direction of arrow P. Here, the linear pulse motor has two sets of cores 5 and 6, each having a pair of magnetic pole teeth and arranged above the scale with the magnetic pole teeth facing the tooth row 4a of the scale 4, and each core 5.6. It is composed of a permanent magnet 7.8 coupled to the back surface, a yoke 9 spanning between the permanent magnets 7 and 8, and an excitation coil 10 wound around the magnetic pole teeth 5a and 6a of the core 5.6. Note that the excitation coil 10 of each core 5.6 is connected in series with the respective pair of magnetic pole teeth with the winding direction being opposite.

The step drive operation with such a configuration is shown in FIGS. 7(a) to (a).
As shown below. That is, the pitches of each magnetic pole tooth and scale tooth row of the core connected by a permanent magnet are arranged in the relationship shown in the figure, and the pitches shown in the figure correspond to the modes (a) to (d). Not controller than each w
By sequentially switching and controlling the input pulse signal l given to the JM1 coil 10, the magnetic flux φ supplied from the permanent magnet is
The magnetic flux φi generated by the magnetic flux and the excitation coil is adjusted for each magnetic pole tooth, and the magnetic flux between the magnetic pole teeth of each core and the scale increases or decreases, which causes the magnetic flux between each magnetic pole tooth and the tooth row on the scale side to increase or decrease. It is well known that the stable position of the object changes sequentially and moves step by step.

[Problem to be solved by the invention]

By the way, in the above-mentioned conventional linear pulse motor, the cores facing each other are arranged vertically above the scale, permanent magnets, yokes, etc. are stacked on top of the cores, and the excitation coil is arranged at the height of the magnetic pole teeth of each core. A linear pulse motor is assembled by winding the wires in the same direction. For this reason, the overall height H of the linear pulse motor becomes large, making it difficult to apply the linear pulse motor to an apparatus in which the overall height including the work mounted on the slider is determined by the installation space.

This invention has been made in consideration of the above points, and its purpose is to significantly reduce the height dimension of a linear pulse motor by changing its structure from the conventional method, thereby making it possible to use a device that is subject to dimensional restrictions in the height direction. The purpose of the present invention is to provide a thin linear pulse motor that can be applied to the following applications.

[Means to solve the problem]

In order to achieve the above object, the linear pulse motor of the present invention has a pair of scales installed on both left and right sides of the slider with tooth rows facing inward, and a pair of scales installed on both left and right sides of the slider opposite to each scale. and a U-shaped core having a pair of magnetic pole teeth opposite to the tooth row of the scale; and a IIJVa coil wound around the core; It consists of a permanent magnet whose magnetic pole surface overlaps the side surface of the magnetic pole teeth and is coupled to the core, and a yoke whose tip overlaps with the back side magnetic pole surface of the permanent magnet and whose tip extends toward the side surface of the scale.

[Effect]

With the above configuration, a closed magnetic path is formed between the permanent magnet, the magnetic pole teeth of the core, the scale, and the yoke, and then returns to the permanent magnet between each set of drive elements arranged on the left and right sides of the slider, and the scale returns to the permanent magnet. By applying an input pulse signal to the excitation coil, the magnetic flux between each magnetic pole tooth and the scale increases or decreases.

Therefore, the slider is driven step by step along the scale by switching and controlling the input pulse signal applied to the excitation coil between the left and right drivers and its direction in a specified mode.

Moreover, by arranging all the components of the linear pulse motor, such as the drive element and scale, on both the left and right sides of the slider, the overall height has been significantly reduced compared to the conventional structure mentioned above. can. By separating the slider from the scale of the linear pulse motor and supporting it on a support guide installed separately, the linear pulse motor can support the entire heavy load including the workpiece with this support guide. It is only necessary to provide propulsion force, and no unreasonable load is applied to the linear pulse motor even if the load weight is large.

[Embodiment] FIGS. 1 to 5 show the structure of an embodiment of the present invention, and the same members corresponding to FIG. 6 are given the same reference numerals. First, the slider 1 on which the workpiece 2 is mounted is made of flat plywood, and the slider 1 is guided and supported by two left and right support guide rods 11 that pass through the plywood.

On the other hand, a pair of scales 4 are installed on both the left and right sides of the slider 1 in parallel with the support guide rod 11, with tooth rows 4a facing inward. It is equipped with two sets of drive elements indicated by 12. Here, between the pair of scales 4, the pitches of the tooth rows 4a are relatively shifted by A pitch.

The driver 12 has a U-shaped core 13 having a pair of magnetic pole teeth 13a and 13b facing the tooth row 4a of the scale 4, and an excitation coil 1 wound around the center of the core 13.
4, a strip-shaped permanent magnet 15 bonded to the top and bottom sides of the core 13 with the tip thereof sandwiched between the pair of magnetic pole teeth 13a and 13b, and a strip-shaped permanent magnet 15 that is superimposed on the back side of the permanent magnet 15 and has a tip end. is constructed as an assembly with two upper and lower yokes 16 provided so as to protrude toward the side surface of the scale 4. The permanent magnet 15 is magnetized in the thickness direction as shown in FIG.
61 One magnetic pole surface (N pole) on the rod teeth 13a and 13b.

The other magnetic pole teeth (S poles) are arranged on the yoke 16 so as to face each other.

Next, FIG. 4 shows the magnetic operation of the drive element 12 with the above configuration.
To explain with reference to FIG. 5, first, each magnetic pole tooth 13a of the core 13,
From the N pole of the permanent magnet 15, there are magnetic pole teeth 13a, tab, and scale 4 between each 13b and the scale 4. yoke 16
Each independent closed magnetic path is formed which returns to the S pole of the permanent magnet 15 via the magnetic field. Here, the magnetic flux supplied from the permanent magnet 15 is indicated by -1 (dotted line).On the other hand, an exciting coil 1 is provided between the U-shaped core 13 and the scale 4 in addition to the closed magnetic circuit described above.
A closed magnetic path including 4 is formed so as to partially overlap with the magnetic path on the permanent magnet side described above. Note that the excitation coil 14
The magnetic fluxes generated corresponding to the positive and negative directions of the input pulse signal l applied to the input pulse signal l are respectively indicated by arrows +φtt-di.

Therefore, when no pulse signal is input to the excitation coil 14, the scale 4 is applied to each magnetic pole tooth 13a, 13b.
A magnetic flux φ- is supplied by a permanent magnet 15 between the two. On the other hand, when a positive pulse signal l is applied to the excitation coil 14, the magnetic flux +φi generated in the excitation coil 14 is superimposed on the magnetic flux φ−, and as a result, the magnetic flux φ is directed to one of the magnetic pole teeth 13a. The magnetic fluxes φ and +φi are added in the same direction, and the magnetic fluxes φ and +φl cancel each other out for the other magnetic pole tooth 13b. On the other hand, when the pulse signal l given to the excitation coil 14 is switched in the negative direction, the magnetic fluxes φ■ and -φi cancel each other out in the magnetic pole teeth 13a, contrary to the above, and the magnetic fluxes φ- and -φl cancel each other out in the magnetic pole teeth 13b. and will be added.

Therefore, as shown in FIG. 1, by sequentially switching the input pulse signal given to the excitation coil 14 between the two sets of drive elements 12 arranged on the left and right sides of the slider 1, and its direction in a specified mode, the teeth of the scale 4 can be adjusted. The magnetically stable position between the row 4a and each set of drive elements 12 changes in the same way as in the conventional permanent magnet type linear pulse motor shown in FIGS. 4, it will move step by step. In this case, work 2
Since the entire load weight of the slider 1 including the slider 1 is carried by the support guide rod 11 shown in FIG. It's over.

Moreover, according to the above configuration, scale 4. Since the drive elements 12 and 12 are all located on both the left and right sides of the slider l, the overall height h (see Figure 2) is significantly reduced compared to the height H of the conventional structure shown in Figure 6. I will do it.

In the illustrated embodiment, permanent magnets and yokes are provided on both upper and lower sides of the magnetic pole teeth of the core for each set of drive elements, but permanent magnets and yokes may be provided only on one side. It is also possible to implement it by Further, in the illustrated example, the tooth row pitch is shifted by A pitch between the left and right scales 4, but instead of aligning the tooth row pitch of the scale 4, the scales are shifted between the two sets of left and right drive elements 12. The mounting position may be shifted by an amount corresponding to two pitches of the tooth row.

〔Effect of the invention〕

As described above, the linear pulse motor of the present invention has a pair of scales installed on both the left and right sides of the slider with the teeth facing inward, and a pair of scales installed on both the left and right sides of the slider facing each scale. It is equipped with two sets of drive elements, and each set of drive elements has a cross-shaped core having a pair of magnetic pole teeth facing the tooth row of the scale, an excitation coil wound around the core, and one magnetic field. By comprising a permanent magnet whose scratching surface overlaps the side surface of the magnetic pole teeth and is coupled to the core, and a yoke which overlaps the magnetic scratching surface on the back side of the permanent magnet and whose tip extends toward the side surface of the scale, The slider can be driven step by step along the scale by switching and controlling the input pulse signals given to the excitation coils of the drive elements, which are separated from each other and placed on both the left and right sides of the slider, in a specified mode. It is possible to provide a thin linear pulse motor that can be reduced in size in the width direction and is particularly advantageous for application to devices subject to restrictions in the height direction.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the configuration 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 the driver in Fig. 1, and Figs. 4 and 5 are respectively An explanatory diagram of the magnetic operation of the drive element, FIG. 6 is a configuration diagram of a conventional linear pulse motor, and FIG. 7 is an explanatory diagram of the operation of FIG. 2: Workpiece, 4 scales, 4a: Teeth row, 12: Drive element, 13: Core, 13a
, 13b: magnetic pole tooth, 14: exciting coil, 15: permanent magnet, 16: yoke, φ crane; magnetic flux supplied from the permanent magnet, +φ1. -φl: Excitation Figure 1, Figure 2, Figure 3, Figure 5

Claims (1)

[Claims] 1) A linear pulse motor that drives a slider on which a workpiece is mounted step by step along a scale using an input pulse signal, and includes a pair of scales installed on both the left and right sides of the slider with teeth facing inward, and a pair of scales installed on each scale. a U-shaped core comprising two sets of drive elements arranged oppositely on the left and right sides of the slider, each set of drive elements having a pair of magnetic pole teeth facing the tooth row of the scale; a permanent magnet coupled to the core with one magnetic pole surface superimposed on the side surface of the magnetic pole teeth, and a permanent magnet superimposed on the back side magnetic pole surface of the permanent magnet with its tip extending toward the side surface of the scale. A linear pulse motor characterized by comprising a yoke and a yoke.