JPH0365042A - Dc linear motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a linear DC motor that is applied as a linear traveling body drive device such as an image scanner such as an optical system of a copying machine.

[Conventional technology]

The above-mentioned linear DC motor has a stator equipped with a field magnet in which N-pole and S-pole are alternately magnetized and a movable element equipped with an armature coil facing each other, and is movable on the guide shaft of the stator. The structure is such that the movable element is moved linearly by fitting one end of the armature and energizing the armature coil.

By the way, various proposals have been made for smoothly linearly moving the mover relative to the stator.

For example, in JP-A-62-48250, a movable element is provided with a plurality of ball bearing pairs and an elastic member is provided for bringing the bearing pairs into contact with a guide shaft on the stator side with a constant load.

[Problem to be solved by the invention]

The conventional technique described above has a problem in that the device becomes expensive because it uses a large number of ball bearings and elastic members.

An object of the present invention is to provide a linear DC motor that can perform smooth linear motion with a simple configuration.

[Means to solve the problem]

The above purpose is to create a north pole along the moving direction of the mover.

A field magnet with multi-pole magnetization of S-poles is provided in the stator, while an air-core armature coil and a position detection element for energizing the armature coil are provided in the movable element.・
This is achieved by arranging the armature coil at a predetermined angle with respect to the field magnet in the attached linear DC motor.

[Effect]

The three-phase armature coil faces the field magnet at a predetermined angle θ, so when a current is applied to the armature coil, the bearing on the mover side moves against the guide shaft on the stator side. A component force is generated in the direction of being pressed.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 2 is a sectional view of the linear DC motor according to the present invention;
The figure is a plan view of a linear DC motor according to the present invention,
1 is a stator, 2 is a movable element, 3 is an armature coil provided on the movable element 2, 4 is provided on the stator l, and adjacent ones are mutually connected in the moving direction of the movable element 2 (in the direction of the arrow in Fig. 3). Field magnets arranged to have different polarities, 5 a guide shaft with a circular cross section provided on the stator I, 6 a motion bearing attached to one end of the mover 2, 7 a guide shaft 5 A supporting member having a rectangular cross section is provided at the end of the stator 1 on the opposite side, 8 is a sliding bearing provided at the other end of the movable element 2 so as to be in sliding contact with the supporting member 7, and 9 is a movement member. This is a locking member for locking the bearing 6 to the movable element 2. Also, stator 1 and mover 2
It also functions as a yoke to configure the magnetic circuit of a linear DC motor.

FIG. 4 shows a configuration taken along line A-A in FIG. 3 to show only the main parts, and 3a, 3b, and 3c are three-phase armature coils,
10a, 10b, 10c are three-phase armature coils 3a, 3
This is a position detection element for determining the energization timing of parts b and 3c.

As mentioned above, the field magnets 4 have a width of P, and are arranged so that adjacent ones have different polarities, but the three-phase armature coils 3 (3a, 3b, 3c) each have a width of 4/3P.
They are arranged in a staggered manner.

Therefore, by passing a current through this armature coil 3, an electromagnetic force acts on the armature coil 3 according to Flegong's left-hand rule, and the armature coil 3 and the mover 2 to which it is fixed move in the magnetic space. do.

Moreover, the position detection elements 10a, 10b, 10c are 4/3P
They are arranged in a staggered manner.

FIG. 1 is a plan view of the arrangement relationship between the armature coil and the field magnet, which are essential parts of the present invention, and the armature coil 3 is inclined at an angle θ with respect to the field magnet 4. Therefore, when current flows through this armature coil 3, vector F
The force of is generated. Of these, the component force F is a thrust force for moving the movable element 2 in a straight line, and the component force Fy is a force for pressing the motion bearing 6 against the guide shaft 5.

5 and 6 are a partially cutaway side view and a partially cutaway front view of the motion bearing, in which 6a is an outer cylinder, 6b is a retainer, and 6C is a steel ball. Although this steel ball 6C makes point contact with the guide shaft 5, a gap is created between the two during assembly. Therefore, normally, the movable element 2 performs linear motion while swinging, causing speed fluctuations, but in the present invention, since the component force Fy acts, this can be suppressed.

〔Effect of the invention〕

As explained above, according to the present invention, since the armature coil is inclined and opposed to the field magnet, when current is applied to the armature coil, the motion bearing of the mover is guided by the stator. To provide a linear DC motor with a simple structure in which a component force is generated to press a shaft, thereby allowing a mover to move smoothly without rocking, and which does not require special members.

[Brief explanation of drawings]

FIG. 1 is a plan view of essential parts of a linear DC motor according to the present invention, FIG. 2 is a cross-sectional view of the linear DC motor according to the present invention, FIG. 3 is a plan view of the linear DC motor according to the present invention, and FIG. A configuration diagram showing only the main parts taken along the line A-A in Figure 3,
5 and 6 are partially cutaway side and front views of the motion bearing. 1... Stator, 2... Mover, 3 (3a, 3b
, 3C)... Armature coil, 4... Field magnet, 10 (10a, 10b, 10c) - Position detection element. Figure 1 Figure 3

Claims (1)

[Claims] The stator is provided with a field magnet that is multi-pole magnetized with N and S poles along the running direction of the mover, and the mover is equipped with an air-core armature coil and this armature coil. 1. A linear DC motor equipped with a position detection element for energizing the motor, wherein the armature coil is arranged at a predetermined angle with respect to the field magnet.