JPH0793809B2 - Linear step motor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a structure of a linear step motor.

(Background Art) Conventionally, as a linear step motor of this type, as described in, for example, Japanese Patent Application Laid-Open No. 269662/1986, a linear pulse motor stator and a mover have been added to provide a very simple mechanism. Noise is prevented in relation to the fluctuation of the magnetic attraction force between the mover and the stator for each step, and not only the linear guide mechanism of the mover is simplified, but also the velocity vibration of the mover is suppressed and noise is reduced. Linear pulse motors have been proposed.

Further, as a linear step motor, as shown in FIGS. 3 (a) and 3 (b), a small tooth 2 is formed on the upper surface of the base 1.
And a guide 3 is erected in parallel so as to sandwich the stator 3.

On the outside of the upper part of the guide 4, the slide guide 5a
And a slide guide 5b is also provided inside the lower surface of the movable body 6, and the slide guides 5a and 5b are slidably slidably in contact with each other.

An iron core 7 is fixed to the lower surface of the movable body 6, and
The coil 8 is formed so that the mover 9 at the tip of the iron core 7 is exposed.
Is wound, and the permanent magnet 10 is mounted on another iron core (not shown) by the movable body 6.

The slide guides 5a and 5b provided on the sliding contact surface between the guide 4 and the movable body 6 are provided in a state where the sliding resistance is close to zero, and the movable element 9 and the stator at the tip of the iron core 7 are provided. The gap with 3 is small and kept constant.

However, as a characteristic of the linear step motor, in order to generate an effective thrust in the moving direction, it is known that a suction force about 10 times the thrust acts between the stator 3 and the mover 9. There is. In addition, the stator 3
It is necessary to have a structure in which a minute and constant gap is maintained between the movable element 9 and the movable element 9, but the movable body 6 to which the movable element 9 is fixed so as to withstand the above-mentioned suction force has a heavy structure. However, there is a problem in that the weight thereof causes a reduction in power performance, and conversely, when the gap between the stator 3 and the mover 9 is relatively large, the thrust is reduced.

(Object of the Invention) The present invention is intended to solve the above-described problems, and reduces the weight of a movable body and the stator and the mover by suppressing the influence of the suction force applied to the stator and the mover. It is an object of the present invention to provide a linear stepping motor with high speed and high acceleration / deceleration by miniaturizing the gap between and.

DISCLOSURE OF THE INVENTION A linear step motor as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 (a) is a perspective view thereof, and FIG. 1 (b) is a front view seen from the moving direction thereof. Two
The figure is a diagram showing the driving state.

The configuration will be described with reference to FIGS. 1 (a) and 1 (b).
Guide guides 16 are erected in parallel on the upper surface of the base 15, and one or a plurality of openings 17 of an arbitrary size are provided in the substantially central portion of the base 15.

Further, the stator 18 is provided on the wall surfaces of the guide guide 16 facing each other, and is composed of small teeth 19a formed of a magnetic material, and a slide guide 20a is provided outside the top of the guide guide 16. There is.

Further, a movable body 21 is provided so as to cover the guide guide 16, and a slide guide 20b is provided inside the movable body 21 and slidably contacts the slide guide 20a.

An iron core 23 is provided so as to sandwich the permanent magnet 22, and is roughly H
The mover 25 at the tip of the pole teeth 24 of the iron core 23 of the die is formed by the small teeth 19b, and the coil 26 is formed so that the mover 25 is exposed.
It is wrapped in.

The movable body 21 and the iron core 23 are fixed so that the stator 18 and the movable element 25 have a constant minute gap, and two sets of four-phase step motor movable elements 25 are fixed to the movable body 21.

The operation of the linear stepping motor having the above-described structure will be described. As shown in FIG. 2, in a certain driving state, the pole teeth 24 of each iron core 23 have the polarities shown in the drawing, and the magnetic path 27 is formed. Then, a suction force acts on each of the movers 25 in a direction perpendicular to the thrust (sliding direction), and this suction force acts on each of the movers 25 as shown by the arrow direction shown in the figure.

This suction power When expressed by Since the suction force acting on each mover 25 is canceled out, the force acting on the mover 25 is almost only thrust (sliding direction).

The same action can be obtained with the other mover 25 whose description is omitted.

Further, in contrast to the conventional case where the suction force acts in the direction perpendicular to the base, in the present invention, the suction force acts in parallel to the base and the suction force is canceled, so that the movable body 21 is bent and the like is taken into consideration. Eliminates the need for heavy manufacturing.

Further, the weight of the movable body 21 can be reduced, and the gap between the stator 18 and the movable element 25 can be easily kept small and constant, so that the thrust can be improved.

Further, since the base 15 is provided with the opening 17, the processing device and the inspection device can be arranged directly below the linear step motor, and the space of the work space can be reduced.

(Effects of the Invention) As described in detail above, according to the linear step motor of the present invention, the following effects and advantages are obtained.

(1) Since the attraction force between the stator and the mover can be canceled out and the force acting on the mover can be made almost only thrust, the rigidity of the moveable body in the vertical direction can be kept relatively low, and The weight can be reduced.

(2) Since there is no influence due to bending of the movable body, the gap between the stator and the movable element can be maintained minute and constant, the thrust can be improved, and a linear step motor with high speed and high acceleration / deceleration can be provided. Can be provided.

(3) By constructing the movable body so as to cover one set of guides, the guide rollers and traveling wheels shown in the conventional device are unnecessary. (4) The guides have small teeth. Since the magnetic pole is provided and the function of guiding the movable body can be shared, the configuration as a linear step motor can be simplified.

[Brief description of drawings]

FIGS. 1 and 2 show a linear step motor of the present invention. FIG. 1 (a) is a perspective view thereof, FIG. 1 (b) is a front view seen from the moving direction thereof, and FIG. 2 is a driving state thereof. FIG. 3 shows a conventional linear step motor, FIG. 3 (a) is a perspective view thereof, and FIG. 3 (b) is a front view seen from the moving direction. 15 …… Base, 16 …… Guide guide, 17 …… Opening, 18…
… Stator, 19a, 19b …… Small teeth, 20a, 20b …… Slide guide, 21 …… Movable body, 22 …… Permanent magnet, 23 …… Iron core, 24…
… Polar teeth, 25 …… movers, 26 …… coils, 27 …… magnetic paths.

Claims (1)

[Claims] 1. A set of guides standing upright in parallel on the upper surface of a base, and small teeth made of a magnetic material, which are integrally formed with the guides and are provided inside the guides facing each other. A stator having; a first slide guide integrally formed with the guide guide and provided outside the guide guide; a movable body provided to cover the set of guide guides; A coil is wound around each of the pole teeth having small teeth provided to face the stator, and the mover is provided between the stator, and the mover is integrated with the mover. Linear step comprising: a first slide guide and a second slide guide provided opposite to the first slide guide, wherein the movable body is movable relative to the guide guide. motor.