JPH0515134A - Stepping motor - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to make a linear motion and a rotary motion simultaneously or independently in a stepping motor used for industrial equipment. [Structure] Having three sets of stators 2, 3 and 4 and one rotor 5 which is slightly longer than the length of the two sets of stators, and changing the combination of the coils of the two sets of adjacent stators of the three sets of stators. Linearly move the position of the rotor 5 by
Further, the rotor 5 is rotated by switching the direction of the exciting current of the selected stator coil, thereby enabling more complicated operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor capable of independently performing a linear movement required for opening and closing a valve for controlling fluid and a rotational movement required for stirring.

[0002]

2. Description of the Related Art In recent years, stepping motors have been used in various industrial equipment due to their good controllability. Particularly, the PM type stepping motor using a permanent magnet for the rotor is inexpensive and widely used.

Conventionally, most stepping motors have only a rotary motion, and the linear motion has been used by converting the rotary motion of the rotor into a linear motion by providing a screw on the shaft.

Hereinafter, those configurations will be described with reference to FIGS. 2 and 3.
Will be described with reference to. As shown in FIG. 2, the conventional P
The M-type stepping motor is composed of a stator 9 and 10 having two sets of windings and a yoke on a frame 8 and one permanent magnet rotor 11. The rotor 11 is rotatably attached to a bearing 13 by a shaft 12.

In the above structure, two sets of stators 9 and 1 are provided.
0 is electrically shifted by 90 degrees, and the excitation of the coils of the first set of stators 9 and the second set of stators 10 is switched to rotate the rotor 11.

When performing linear movement, screws are provided on the shaft 14 and the rotor 15 as shown in FIG. 3, and the rotor 15 is rotated to generate linear movement on the shaft 14. In this case, the shaft 14 does not rotate but only moves linearly. Further, there is also a device in which a screw is provided at the tip of the shaft 14 and is combined with a screw provided on a moving object to linearly move the object (not shown).

[0007]

In such a conventional stepping motor, the motion generated in the shaft is either a rotary motion or a linear motion.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a stepping motor that allows a shaft to perform linear movement and rotary movement simultaneously or independently.

[0009]

In order to achieve the above object, the present invention has a structure having one permanent magnet rotor and a stator composed of windings and yokes wound around three or more sets of coil bobbins. It is a thing.

[0010]

According to the present invention, the position of the rotor is moved linearly by changing the combination of the coils of two adjacent stators of three or more stators.
The rotor is rotated by switching the excitation of the coils of the pair of stators. That is, the shaft can be operated independently of linear movement and rotational movement.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. As shown in the figure, the frame 1 is composed of three sets of stators 2, 3, 4 and one permanent magnet rotor 5, and the rotor 5 is rotatably attached to a bearing 7 by a shaft 6. Each of the three sets of stators has a coil for excitation, and they are arranged so as to be deviated from each other by an electrical angle of 90 degrees. Excitation of the pole teeth is the same as that of the conventional stepping motor. And the rotor 5 is 2
It is slightly longer than the length of the pair of stators and has a structure that allows axial movement.

The operation of the above structure will be described. When the rotor 5 is in the holding state at the position shown in the drawing, the coils of the first set of stators 2 are de-energized and the coils of the third set of stators 4 are energized. Center off, rotor 5
Moves to the bottom of the figure. Further, in the hold state, the excitation of the two sets of coils is switched in the same manner as in a normal stepping motor, so that the rotor 5 can be rotated without changing the position of the rotor 5.

As described above, according to the stepping motor of the embodiment of the present invention, the linear motion is combined by changing the combination of the coils of two adjacent stators.
Rotational motion can be performed independently by switching the excitation of the coils of the pair of stators.

In this embodiment, the number of stator sets is three, but the same applies to the case where the number of stator sets is more than that. If the number of stator sets is increased, finer control or a large movement amount can be obtained.

[0015]

As is apparent from the above description of the embodiments, according to the present invention, one permanent magnet rotor and three or more sets of stators are provided, and the shaft independently performs rotation and linear motion. Since it is performed, a more complicated operation is possible than when it is used for a valve or the like.

[Brief description of drawings]

FIG. 1 is a sectional view of a stepping motor of the present invention.

FIG. 2 is a sectional view of a conventional stepping motor.

FIG. 3 is an explanatory diagram of linear motion of the stepping motor.

[Explanation of symbols]

 1 frame 2 1st set stator 3 2nd set stator 4 3rd set stator 5 rotor 6 shaft

Claims (1)

Claim: What is claimed is: 1. A permanent magnet rotor and a stator composed of a coil wound around three or more sets of coil bobbins and a stator, and changing the combination of the coils and switching the coils. A stepping motor having means for allowing the motor shaft to perform two independent movements, a rotary movement and a linear movement.