KR101617244B1 - Linear motor capable of absolute position measurement - Google Patents

Abstract

The present invention relates to a linear motor capable of absolute position measurement, and more particularly, to a linear motor capable of measuring an absolute position of a mover using a Hall sensor passing through a reference portion having a different magnetic field intensity.

Description

[0001] LINEAR MOTOR CAPABLE OF ABSOLUTE POSITION MEASUREMENT [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor capable of absolute position measurement, and more particularly, to a linear motor capable of measuring an absolute position of a mover using a Hall sensor passing through a reference part having a different magnetic field strength.

A linear motor is a linearly driven motor, which is a structure in which a rotating motor is cut and unfolded. That is, it is a driving device that has the same structure as that developed on a plane cut along an axis of an electric motor, and a current is made to flow through a coil placed between the magnets arranged in a row to obtain a force.

And is constituted by a stator and a mover, and generates a linear driving force of the mover.

The advantage of linear motors is that they are much used in aviation, etc., because they have less vibration and dust than rotating motors.

Linear motors require precise control of absolute position and relative position of the mover.

If the initial position of the mover is known, it is possible to control the linear motor with only the relative position. However, if the initial position of the mover is not known at the time of power supply, it is impossible to precisely control the linear motor with the relative position.

When a hall sensor is used as a sensor for measuring a relative position, it is general that a hall sensor is provided in a linear motor and a sensor for measuring an absolute position of the mover is provided outside the linear motor.

That is, there is a problem that the relative position sensor and the absolute position sensor are biased to each other, the configuration is complicated, and the wiring becomes complicated.

Korean Patent Laid-Open Publication No. 10-2002-0086275 discloses a linear motor.

Korean Patent Publication [10-2002-0086275] (Publication Date: November 18, 2002)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a linear motor in which a sensor for measuring an absolute position is not additionally installed, And to provide a linear motor capable of performing absolute position measurement capable of measuring an absolute position as well as a relative position of the mover.

According to an aspect of the present invention, there is provided a linear motor capable of absolute position measurement, wherein a magnetic material of N pole and S pole is alternately stacked in the longitudinal direction, An arrayed magnetic portion 110; A reference portion 120 connected to the magnetic force portion 110 and made of a material that forms a magnetic force different from the magnetic force of the magnetic substance constituting the magnetic force portion 110; A magnetic part (100) including the magnetic part (110) and the reference part (120); A core part 200 parallelly spaced apart from the magnetic part 100 and having a plurality of coil parts 210 wound with coils 211 arranged in the longitudinal direction; A sensor unit 300 including two or more Hall sensors 310 provided on the outer surface of the core unit 200 on the side of the magnetic part 100; A position measuring unit 400 for measuring a position of at least one of an absolute position and a relative position of the magnetic part 100 or the core part 200 based on the Hall sensors 310 of the sensor part 300; Wherein at least one Hall sensor 310 of the Hall sensors 310 of the sensor unit 300 is configured to sense the reference portion 120 when the magnetic portion 100 or the core portion 200 reciprocates, And is installed at a position that passes through the center.

Also, a plurality of the reference portions 120 are formed.

In addition, the magnetic portion 100 and the core portion 200 are cylindrical.

In addition, when the magnetic part 100 or the core part 200 reciprocates, the arrangement of the reference part 120 and the hall sensor 310 may be such that at least one hall sensor 310 in every section has at least one Is disposed so as to pass through the reference portion (120).

According to the linear motor capable of absolute position measurement according to the embodiment of the present invention, even if a sensor for measuring the absolute position is not additionally mounted to the outside of the linear motor, It is possible to measure the absolute position of the mover (armature), so that the structure of the linear motor can be simplified, the wiring can be simplified, and convenience and economy can be improved.

By constituting a plurality of reference portions, it is possible to extend a section in which the absolute position can be measured.

In addition, since at least one hall sensor is arranged to pass through at least one reference portion in every section, it is possible to measure the absolute position in all sections.

In addition, the linear linear motor actuator may cause errors even when the stator and the mover are slightly rotated. However, by forming the magnetic portion and the core portion (stator and mover) into a cylindrical shape, it is possible to reduce the occurrence of errors as compared with the linear linear motor actuator There is an effect that can be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual view showing an embodiment in which a reference portion is formed at a left end of a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG.
FIG. 2 is a conceptual diagram showing an embodiment in which a reference portion is formed at a right end in a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG.
3 is a conceptual view showing an embodiment in which a reference portion is formed at the center in a linear motor capable of absolute position measurement according to an embodiment of the present invention.
4 is a conceptual diagram showing an embodiment in which a plurality of reference portions are formed in a linear motor capable of absolute position measurement according to an embodiment of the present invention.
FIG. 5 is a conceptual diagram showing an embodiment in which a magnetic portion and a core portion are formed in a cylindrical shape, and a magnetic portion serves as a stator, in a linear motor capable of absolute position measurement according to an embodiment of the present invention.
FIG. 6 is a conceptual view showing an embodiment in which a magnetic portion and a core portion are formed in a cylindrical shape, and the core portion serves as a stator, in a linear motor capable of absolute position measurement according to an embodiment of the present invention.
FIG. 7 is a conceptual diagram showing that an absolute position and a relative position of a linear motor constituted by three Hall sensors can be measured with respect to a mover, in a linear motor capable of absolute position measurement according to an embodiment of the present invention.
FIG. 8 is a conceptual diagram showing that an absolute position of a linear motor composed of two hall sensors can be measured in all sections in a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG.
FIG. 9 is a conceptual diagram showing that the absolute position of a linear motor composed of three Hall sensors can be measured in all sections in a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG.

Hereinafter, the present invention will be described in more detail with reference to the drawings. The following drawings are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the following drawings, but may be embodied in other forms. In addition, like reference numerals designate like elements throughout the specification. It is to be noted that the same elements among the drawings are denoted by the same reference numerals whenever possible. Further, it is to be understood that, unless otherwise defined, technical terms and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

FIG. 1 is a conceptual view showing an embodiment in which a reference portion is formed at a left end of a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG. 2 is a schematic view illustrating an absolute position measurement according to an exemplary embodiment of the present invention. FIG. 3 is a conceptual diagram showing an embodiment in which a reference portion is formed at the center in a linear motor capable of absolute position measurement according to an embodiment of the present invention; FIG. And FIG. 4 is a conceptual diagram showing an embodiment in which a plurality of reference portions are formed in a linear motor capable of performing absolute position measurement according to an embodiment of the present invention. In a linear motor, a conceptual view showing an embodiment in which a magnetic portion and a core portion are formed in a cylindrical shape and a magnetic portion serves as a stator, 7 is a conceptual diagram showing an embodiment in which a magnetic portion and a core portion are formed into a cylindrical shape and a core portion serves as a stator in a linear motor capable of absolute position measurement according to an embodiment of the present invention. FIG. 8 is a conceptual diagram showing a linear motor capable of measuring an absolute position according to an embodiment of the present invention, in which a linear motor composed of three Hall sensors can measure an absolute position and a relative position with respect to a mover. FIG. 9 is a conceptual diagram showing a linear motor capable of absolute position measurement, in which the absolute position of a linear motor constituted by two hall sensors can be measured in all the sections. FIG. 9 is a conceptual diagram showing an absolute position It is shown that the absolute position of the linear motor with 3 Hall sensors can be measured in all the segments in the linear motor which can be measured. Yeoju is a conceptual diagram.

1 to 3, a linear motor capable of absolute position measurement according to an embodiment of the present invention includes a magnetic part 110 and a reference part 120, And at least one Hall sensor 310 of the Hall sensors 310 of the sensor unit 300. The hall sensor 310 may include a magnetic sensor 100, a core unit 200, a sensor unit 300, and a position measuring unit 400, Is installed at a position passing through the reference part (120) when the magnetic part (100) or the core part (200) reciprocates.

The reason why the at least one hall sensor 310 is installed at the position passing the reference portion 120 is that the absolute position can be measured when the hall sensor 310 passes the reference portion 120.

The magnetic portion 100 includes the magnetic portion 110 and the reference portion 120.

The magnetic portion 110 is formed by alternately stacking N magnetic poles and S magnetic poles in the longitudinal direction.

In other words, as shown in FIG. 1, the magnetic material of the N pole and the magnetic material of the S pole are arranged in an alternating arrangement, and the magnetic material of the N pole and the magnetic material of the N pole, The magnetic substances of the S-pole are arranged in an intersecting manner, but can be closely attached. Here, the magnetic substance refers to a substance having a magnetic force, and examples thereof include permanent magnets and the like.

The reference portion 120 is formed of a material that is connected to the magnetic force portion 110 and forms a magnetic force different from a magnetic force of the magnetic material constituting the magnetic force portion 110.

At this time, the reference portion 120 may be located at the left end (see FIG. 1), the right end (see FIG. 2), and all other portions (see FIG.

For example, when the magnetic force of the N or S poles constituting the magnetic force unit 110 is assumed to be 10, the reference unit 120 may be made of a material having magnetic force of 0, 5, or 15 . Here, a substance having a magnetic force of 0 is generally a material that does not have a magnetic force (magnetic property), and examples thereof include ceramics and the like.

The core part 200 is disposed parallel to the magnetic part 100 at a predetermined interval and many coil parts 210 in which the coil 211 is wound are arranged in the longitudinal direction.

For example, a plurality of slots may be arranged at predetermined intervals on the outer circumferential surface of the core portion 200 formed in the longitudinal direction, and one coil portion 210 in which the coil 211 is wound in one slot may be disposed .

The sensor unit 300 includes two or more Hall sensors 310 provided on the outer surface of the core unit 200 on the side of the magnetic unit 100.

The Hall sensor is made of a very thin semiconductor plate mainly by attaching a semiconductor piece having a thickness of about 0.5 μm to 100 μm onto a ceramic or plastic substrate or by thinly coating the substrate with a thickness of about 2 μm to 3 μm.

When a voltage is applied in the longitudinal direction (e.g., the transverse direction) of the semiconductor plate, the current I moves electrons at a very high speed. At this time, when magnetic flux is passed in the direction perpendicular to the current, electric charge is biased to the side by the Lorentz force. Therefore, a voltage U _H of several hundreds mV is generated at the other ends (e.g., the longitudinal direction) of the substrate. This voltage is called a Hall voltage.

The Hall voltage U _H is proportional to the current I and the magnetic flux density B and changes according to the (Hall constant: R _H ) and the thickness d of the semiconductor plate.

The hall sensor generates the Hall voltage U _H from the current I and the magnetic flux density B.

Speaking of the Hall voltage U _H [V], the current I [A], the magnetic flux density B [Wb], the Hall constant R _H [m3 / As], the thickness of the semiconductor board d [m], the Hall voltage U _H [V] is expressed by the following equation.

The position measuring unit 400 measures the position of at least one of an absolute position and a relative position of the magnetic unit 100 or the core unit 200 based on the hall sensors 310 of the sensor unit 300.

Knowing how many N-poles and S-poles the hall sensor has passed can tell how much the mover has moved (its relative position). At this time, the relative position can be used as data for giving a signal for driving the motor. For example, if the N pole and the S pole are provided at intervals of 1 cm and the mover is moved by 4 cm to the right, if the hall sensor is controlled to stop passing through the two N poles and the two S poles from the current position to the right The mover can be moved 4 cm to the right.

According to the linear motor capable of absolute position measurement according to the embodiment of the present invention, even if a sensor for measuring the absolute position is not additionally mounted to the outside of the linear motor, It is possible to measure the absolute position of the mover (armature), so that the structure of the linear motor can be simplified, thereby simplifying the wiring.

As described above, the reason why the structure of the linear motor is simplified is that it is used for applications requiring a simple configuration to minimize the volume and minimize the occurrence of problems such as aviation.

As shown in FIG. 4, a plurality of reference portions 120 of a linear motor capable of absolute position measurement according to an embodiment of the present invention may be formed.

That is, as the area occupied by the reference unit 120 increases, the area where the absolute position can be measured is increased. Therefore, in order to monitor the more accurate absolute position value, the area occupied by the reference unit 120 may be increased, ) Can be increased.

As shown in FIGS. 5 to 7, the magnetic portion 100 and the core portion 200 of the linear motor capable of absolute position measurement according to an embodiment of the present invention may be cylindrical. Here, the cylindrical shape includes a ring shape.

For example, as shown in FIG. 5, a cylindrical magnetic portion 100 having an N-pole magnetic substance and an S-pole magnetic substance arranged in an intersecting manner is used as a stator (shaft) The cylindrical core portion 200 surrounding the magnetic portion 100 can be configured to be used as a mover (armature).

Further, as shown in FIG. 6, a plurality of cylindrical slots formed perpendicularly to the longitudinal direction are arranged at predetermined intervals in the longitudinal direction, and a coil part 210 in which the coil 211 is wound is disposed in each slot The core portion 200 may be used as a stator and the cylindrical magnetic portion 100 surrounding the cylindrical core portion 200 may be used as a mover.

Although FIGS. 5 and 6 illustrate the cylindrical magnetic portion 100 in which the N-pole magnetic material and the S-pole magnetic material are arranged in close contact with each other, the N-pole magnetic material and the S- Needless to say, it is also possible to use cylindrical magnetic portions 100 spaced apart from each other by a predetermined distance.

FIG. 7 shows that the absolute position and relative position of the linear motor composed of three hall sensors 310 can be measured with reference to the configuration of FIG.

More specifically, the Hall sensor 310 is constituted by three Hall sensors (composed of (1), (2), and (3)), and the core portion reciprocates from the position a to the position g.

(1) the measured value of the hall sensor, (2) the measured value of the Hall sensor, (3) the measured value of the Hall sensor, The absolute position can be confirmed on the basis of the measured value of the hall sensor in the section C, and the relative position can be confirmed in the section B.

8 to 9, the arrangement of the reference portion 120 and the hall sensor 310 of the linear motor capable of absolute position measurement according to an embodiment of the present invention is similar to that of the magnetic portion 100 or the core At least one Hall sensor 310 may be arranged to pass through at least one reference part 120 in all sections when the part 200 reciprocates.

This is to measure absolute position in all sections. Relative position measurement is also possible in the section where absolute position measurement is possible.

For example, as shown in FIG. 8, when the Hall sensor 310 is constituted by two Hall sensors (the hall sensors constituted of (1), (2)) and the core part reciprocates from the position a to the position e, Absolute position can be measured in all sections from a to e.

9, the hall sensor 310 is constituted by three Hall sensors (1), (2), and (3)), and the core portion reciprocates from the position a to the position g , The absolute position can be measured in all the intervals a to g.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100:
110:
120: Reference part
200: core part
210: coil part
211: Coil
300:
400:

Claims (4)

In a linear motor capable of absolute position measurement,
A magnetic field portion 110 in which magnetic substances of N poles and S poles are alternately stacked in the longitudinal direction;
A reference portion 120 connected to the magnetic force portion 110 and made of a material that forms a magnetic force different from the magnetic force of the magnetic substance constituting the magnetic force portion 110;
A magnetic part (100) including the magnetic part (110) and the reference part (120);
A core part 200 parallelly spaced apart from the magnetic part 100 and having a plurality of coil parts 210 wound with coils 211 arranged in the longitudinal direction;
A sensor unit 300 including two or more Hall sensors 310 provided on the outer surface of the core unit 200 on the side of the magnetic part 100; And
A position measuring unit 400 for measuring a position of at least one of an absolute position and a relative position of the magnetic part 100 or the core part 200 based on the hall sensors 310 of the sensor part 300;
, ≪ / RTI &
The reference portion 120 is made of a material having a magnetic force different from that of the magnetic force portion 110,
The arrangement of the reference part 120 and the hall sensor 310 is such that at least one Hall sensor 310 is installed in at least one reference part And one Hall sensor 310 is disposed at the end of the sensor unit 300 or at least one coil part 210 therebetween,
The position measuring unit 400 may be configured to measure the position of the Hall sensor 310 based on the fact that the measured value of the Hall sensor 310 changes when the hall sensor 310 passes the reference unit 120, Confirms the absolute position of the core portion 200 with respect to the magnetic portion 100,
Wherein the Hall sensor (310) is a 0.5μm to 100μm thick semiconductor piece attached on a plastic substrate, or a 2μm to 3μm thick semiconductor plate clad on the substrate.
The method according to claim 1,
The reference portion 120
Wherein a plurality of linear motors are formed.
The method according to claim 1,
The magnetic part (100) and the core part (200)
A linear motor capable of absolute position measurement characterized by being cylindrical.
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