JPS61180564A - Linear pulse motor - Google Patents

Abstract

PURPOSE:To decrease the cost and the size due to reductions in machining and assembling accuracies by engaging a bearing member formed by bending a self-lubricating polymer sheet in a cylindrical shape with the outer periphery of a movable element, and slidably supporting on the inner surface of the pole of a stator. CONSTITUTION:A linear pulse motor slidably supports a movable element 2 in a cylindrical stator 1. The stator 1 is formed with a ring-shaped or spiral pole teeth 11 on the inner periphery, and closed at both end opening surfaces by side plates. The element 2 is constructed by integrally engaging a permanent magnet 21 with the axial center, yokes 22a, 22b with both sides, winding coils 23 on the outer peripheral surfaces of the yokes 22a, 22b and forming pole teeth 24-27 at both sides of the coils 23. A bearing member 3 is wound on the outer periphery of the element 2 by bending a self-lubricating polymer sheet material in a cylindrical shape and securing.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a cylindrical linear pulse motor applied to, for example, a floppy head drive of a word processor.

<Summary of the Invention> The present invention includes a bearing member made of a self-lubricating polymer sheet material bent into a cylindrical shape fitted over the entire circumferential surface of a slider, and a bearing member that is slidably mounted on the inner surface of the magnetic pole teeth of a cylindrical stator. By doing so, a special bearing can be omitted and the configuration can be simplified, downsized, and costs significantly reduced.

<Background of the invention> Conventionally, as shown in FIG. The stator 7 is slidably supported on the shaft, and side plates 52 and 53 are provided on the open surfaces of both ends of the stator 5.
It has been proposed to close the hole by press-fitting it or fixing it with adhesive (Utility Model Application No. 58-97759). In such a conventional structure, the guide shaft 51 . The bearing 6 and the bearing bush 61 of the slider 7 increase the motor diameter, and the bearing 6
uses particularly expensive circulating linear ball bearings, which contributes to the high cost of linear motors.

Furthermore, during processing and assembly, the stator 5 and the end plate 52
, 53, the clearance between the guide shaft 51 and the bearing 6, the concentric accuracy between the slider 7 and the bearing 6, etc. all require high precision, resulting in extremely low productivity and high cost. This is a factor in the increase.

<Objective of the Invention> An object of the present invention is to eliminate special parts such as guide shafts and bearings, and to realize cost reduction and miniaturization by reducing machining and assembly accuracy.

<Configuration and Effects of the Invention> In order to achieve the above object, the present invention includes a bearing member made of a self-lubricating polymer sheet material bent into a cylindrical shape fitted to the outer peripheral surface of the mover, and It is slidably supported on the inner surface of the tooth.

According to the above structure, the bearing member on the outer periphery of the slider is directly supported by the stator 1 and slides smoothly.Compared to the conventional structure, the guide shaft and bearings are omitted, which makes the motor smaller and the processing and assembly work easier. This has the effect of achieving the intended purpose of realizing cost reduction through

<Description of Embodiments> FIG. 1 shows a linear pulse motor according to the present invention. The linear pulse motor includes a mover 2 inside a cylindrical stator 1.
is slidably mounted on a bearing. The stator 1 has ring-shaped or spiral magnetic pole teeth 11 formed on its inner peripheral surface, and both open ends are closed with side plates 12 and 13.

The mover 2 includes a permanent magnet 21 at the center in the axial direction, and yokes 22a and 22b sandwiching the permanent magnet 21- on both sides in the axial direction.
are fitted integrally, and a concave groove that goes around once in the center of the axial direction is provided on the outer periphery of both yokes 22a and 22b, and a coil 23.23 is wound around it. It forms magnetic pole teeth 24, 25, 26, 27. The above permanent magnet 21, each coil 23.23, magnetic pole teeth 24.25
．． A bearing member 3, which is a feature of the present invention, is fitted onto the outer periphery of the mover 2 including 26 and 27, and is slidably supported on the inner surface of the magnetic pole teeth 11 of the stator 1.

The bearing member 3 is made of a self-lubricating polymer sheet material such as Teflon-based or molybdenum disulfide-based material having a small friction coefficient, bent into a cylindrical shape and attached to the outer peripheral surface of the slider 2, as shown in FIG. The outer diameter of the bearing member is the same as the magnetic pole tooth 1 of the stator 1.
1 corresponds to the inner diameter.

The magnetic pole teeth on the outer periphery of the yokes 22a and 22b are based on the 1-phase magnetic pole teeth 24 with respect to the magnetic pole teeth 11 of the stator.
■The phase separation pole teeth 25 are 1/2 pitch ■The phase magnetic pole teeth 26 are 1/4
Pitch, ■ phase separation The polar teeth 27 are shifted in phase by 3/4 pitch.

As described above, in the present invention, the bearing member 3 made of a self-lubricating polymer sheet material bent into a cylindrical shape is fitted on the outer periphery of the mover 2, so that it can directly slide on the inner surface of the magnetic pole teeth 11 of the cylindrical stator 2. Because of the bearing, the guide shaft, bearing, and bearing bushing are omitted compared to linear pulse motors that use conventional linear ball bearings, and the cost is significantly reduced due to the miniaturization of linear pulse motors and the simplified number of parts, processing, and assembly work. It is possible to achieve down.

Furthermore, in a linear pulse motor, if the magnetic gap is uneven, a magnetic attraction force acts in the radial direction, increasing frictional force and having a negative effect on stopping accuracy. In the bearing member 3, the sheet thickness of the polymer sheet material constituting the bearing member 3 can be easily set with high precision, and the bearing gap between the stator 1 and the slider 2 can be set with high precision. The suction force is also small, which has the effect of significantly improving the distance between stops.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the linear pulse motor of the present invention, FIG. 2 is a perspective view showing a state in which a bearing member is fitted to a slider, and FIG. 3 is a sectional view of a conventional linear pulse motor. 1... Stator 11... Magnetic pole teeth 2... Mover 21... Permanent magnets 22a, 22b...
・Yoke 23...Coil 24.25, 26.27・
...Magnetic pole tooth 3...Bearing member.

Claims (2)

[Claims] (1) In a linear pulse motor consisting of a cylindrical stator with magnetic pole teeth on the inner circumferential surface and a slider disposed inside the stator and with magnetic pole teeth on the outer circumferential surface, the slider has self-lubrication. A linear pulse motor is constructed by fitting a bearing member made of a cylindrical polymer sheet material into a cylindrical shape and slidably supporting the magnetic pole teeth of a stator. (2) The linear pulse motor according to claim 1, wherein the bearing member is a polymer sheet material such as Teflon or molybdenum disulfide.