Patent Description:
In general, a magnetic bearing is configured to serve as a bearing. In the magnetic bearing, magnets or electromagnets with high magnetism are disposed around a rotary shaft, and a suspended body provided in a direction perpendicular to the rotary shaft is levitated by magnet.

More specifically, unlike a general ball bearing in the related art, the magnetic bearing is configured such that the suspended body is supported in the air by a magnetic force in a contactless manner without being in direct contact with a rotary body so that the suspended body may rotate or rectilinearly move.

Because the bearings in the related art often cause friction made by contact, the magnetic bearings for minimizing friction have been recently used in various fields.

In the case of the magnetic bearing, an axial displacement of a rotary body needs to be measured to prevent contact between the suspended body and the magnet and control an accurate operation of the bearing.

<FIG> is an exemplified view of a sensor for controlling a displacement of a magnetic bearing in the related art.

As illustrated in <FIG>, a magnetic bearing <NUM> in the related art requires a separate installation space for a sensor <NUM> because the sensor <NUM> needs to be installed at a side of the bearing <NUM> including an electromagnet.

In addition, in case that the sensor <NUM> is positioned at the side of the bearing <NUM> as illustrated in <FIG>, the suspended body and the sensor <NUM> are not colocatedly positioned and aligned, which cause problems in that the accuracy in measuring a displacement deteriorates, and there is a difficulty in designing and controlling the bearing.

Accordingly, there is a need for a magnetic bearing having a colocated eddy-current displacement sensor to reduce a sensor installation space and manufacturing costs and solve a problem of sensor noise.

The document <CIT> discloses a magnetic bearing having sensors located on separated teeth between two electromagnets.

The document <CIT> discloses also a magnetic bearing with sensors coupled to the inside portion of the teeth supporting the electromagnets.

An object of the present invention for solving the above-mentioned problems is to provide a magnetic bearing having a colocated eddy-current displacement sensor that reduces a sensor installation space and manufacturing costs and solves a problem of sensor noise.

Technical problems to be solved by the present invention are not limited to the above-mentioned technical problems, and other technical problems, which are not mentioned above, may be clearly understood from the following descriptions by those skilled in the art to which the present invention pertains.

A configuration of the present invention for achieving the above-mentioned object provides a magnetic bearing having a colocated eddy-current displacement sensor, the magnetic bearing including: an electromagnet unit including a circular casing having a hollow portion therein, and a plurality of electromagnets disposed along an inner periphery of the casing; an amplifier unit coupled to one side of the electromagnet unit; a coil wiring unit coupled to the other side of the electromagnet unit; and a plurality of sensor units disposed along an inner periphery of the electromagnet unit and each having two opposite ends respectively coupled to the coil wiring unit and the amplifier unit, the plurality of sensor units being provided between the coil wiring unit and the amplifier unit, in which the sensor unit is disposed colocatedly with a suspended body supported by the electromagnet unit and configured to measure a displacement of the suspended body.

According to the embodiment of the present invention, the electromagnet unit may include: a vertical frame provided between the casing and the electromagnet and extending toward the coil wiring unit and the amplifier unit; and a horizontal frame provided at an end of the vertical frame and coupled to the coil wiring unit and the amplifier unit.

According to the embodiment of the present invention, the sensor unit may include: a sensor substrate configured as a PCB; a sensor coil provided on the sensor substrate; and protrusion bodies protruding from four corners of the sensor substrate in a longitudinal direction of the sensor substrate, and the protrusion bodies may be provided to be fitted into holes formed in the coil wiring unit and the amplifier unit.

According to the embodiment of the present invention, the magnetic bearing may further include: a support unit coupled between the sensor unit and the casing and extending to have a length corresponding to the sensor unit, in which the support unit is disposed in a direction orthogonal to the sensor unit.

According to the embodiment of the present invention, the sensor unit may include: a center hole formed at a center of a sensor substrate configured as a PCB; and edge holes formed at two opposite ends based on a longitudinal direction of the sensor substrate, and the support unit may be provided to be fitted into the center hole and the edge holes.

According to the embodiment of the present invention, the magnetic bearing may further include a reinforcement unit having two opposite ends coupled to the coil wiring unit and the amplifier unit.

According to the embodiment of the present invention, the electromagnet unit may further include a column part provided between the casing and the coil wiring unit, and the column part may be provided as a plurality of column parts provided along a periphery of the other side surface of the casing.

According to the embodiment of the present invention, the magnetic bearing may further include a coupling unit configured to further couple and fix the sensor unit to the horizontal frame.

According to the embodiment of the present invention, the sensor unit may include: a sensor substrate configured as a PCB; a sensor coil provided on the sensor substrate; and fitting holes formed at four corners of the sensor substrate.

According to the embodiment of the present invention, the coupling unit may include: a coupling body configured to define a body and extending in a direction parallel to the sensor substrate; a pair of fitting bodies extending toward the fitting holes disposed adjacent to two opposite ends of the coupling body and fitted into the fitting holes; and a pair of fixing bodies extending from the two opposite ends of the coupling body and extending to be respectively coupled to the adjacent horizontal frames.

According to the effect of the present invention configured as described above, it is possible to reduce a sensor installation space and manufacturing costs and solve a problem of sensor noise.

In addition, according to the present invention, the sensor unit is assembled by fitting, which makes it easy to assemble and disassemble the sensor unit.

In addition, according to the present invention, the support unit supports the sensor unit while being oriented in a direction orthogonal to the sensor unit. Therefore, even in case that the electromagnet unit rotates, it is possible to prevent the sensor substrate from being bent or deformed.

The effects of the present invention are not limited to the above-mentioned effects, and it should be understood that the effects of the present invention include all effects that may be derived from the detailed description of the present invention or the appended claims.

The most exemplary embodiment according to the present invention provides a magnetic bearing having a colocated eddy-current displacement sensor, the magnetic bearing including: an electromagnet unit including a circular casing having a hollow portion therein, and a plurality of electromagnets disposed along an inner periphery of the casing; an amplifier unit coupled to one side of the electromagnet unit; a coil wiring unit coupled to the other side of the electromagnet unit; and a plurality of sensor units disposed along an inner periphery of the electromagnet unit and each having two opposite ends respectively coupled to the coil wiring unit and the amplifier unit, the plurality of sensor units being provided between the coil wiring unit and the amplifier unit, in which the sensor unit is disposed colocatedly with a suspended body supported by the electromagnet unit and configured to measure a displacement of the suspended body.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different ways and is not limited to the embodiments described herein. Further, a part irrelevant to the description will be omitted in the drawings in order to clearly describe the present invention, and similar constituent elements will be designated by similar reference numerals throughout the specification.

Throughout the present specification, when one constituent element is referred to as being "connected to (coupled to, in contact with, or linked to)" another constituent element, one constituent element can be "directly connected to" the other constituent element, and one constituent element can also be "indirectly connected to" the other element with other elements interposed therebetween. In addition, unless explicitly described to the contrary, the word "comprise/include" and variations such as "comprises/includes" or "comprising/including" will be understood to imply the inclusion of stated elements, not the exclusion of any other elements.

The terms used in the present specification are used only for the purpose of describing particular embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless clearly described as different meanings in the context. In the present specification, it should be understood the terms "comprises," "comprising," "includes," "including," "containing," "has," "having" or other variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Hereinafter, the embodiment of the present invention will be described with reference to the accompanying drawings.

<FIG> is a perspective view illustrating an amplifier unit of a magnetic bearing having a colocated eddy-current displacement sensor according to a first embodiment of the present invention, and <FIG> is a perspective view illustrating a coil wiring unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the first embodiment of the present invention.

<FIG> is a perspective view illustrating a state in which the amplifier unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the first embodiment of the present invention is detached, <FIG> is an enlarged perspective view of a sensor unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the first embodiment of the present invention, and <FIG> is a perspective view of the sensor unit according to the first embodiment of the present invention.

Referring to <FIG>, a magnetic bearing <NUM> having a colocated eddy-current displacement sensor according to a first embodiment includes an electromagnet unit <NUM>, an amplifier unit <NUM>, a coil wiring unit <NUM>, sensor units <NUM>, support units <NUM>, and reinforcement units <NUM>.

The electromagnet unit <NUM> includes a casing <NUM>, electromagnets <NUM>, vertical frames <NUM>, and horizontal frames <NUM>.

The casing <NUM> may be formed as a circular frame having a hollow portion formed therein.

The electromagnet <NUM> may be provided as a plurality of electromagnets <NUM> disposed along an inner periphery of the casing <NUM>. The electromagnet and a permanent magnet may be disposed to generate a magnetic force according to a flow of an electric current.

A suspended body may be provided to be rotatable while being floated in the hollow portion in the casing <NUM> by the electromagnets <NUM>.

The vertical frame <NUM> may be provided between the casing <NUM> and the electromagnet <NUM> and extend toward the coil wiring unit <NUM> and the amplifier unit <NUM>.

Specifically, the vertical frames <NUM> may extend toward the casing <NUM> and the coil wiring unit <NUM> and toward the casing <NUM> and the amplifier unit <NUM>.

Alternatively, the single vertical frame <NUM> may extend toward the coil wiring unit <NUM> and the amplifier unit <NUM>.

The horizontal frame <NUM> may be provided at an end of the vertical frame <NUM> and coupled to the coil wiring unit <NUM> and the amplifier unit <NUM>.

Specifically, the horizontal frame <NUM> may extend from the end of the vertical frame <NUM> and have a predetermined length in a direction parallel to the coil wiring unit <NUM> and the amplifier unit <NUM>.

The vertical frames <NUM> and the horizontal frames <NUM> fixedly couple the casing <NUM> and the amplifier unit <NUM> and fixedly couple the casing <NUM> and the coil wiring unit <NUM>.

The amplifier unit <NUM> may be coupled to one side of the electromagnet unit <NUM>. The amplifier unit <NUM> may be manufactured as a PCB. The amplifier unit <NUM> may be provided in the form of a circular plate having a hollow portion therein and corresponding to a shape of the casing <NUM>.

The coil wiring unit <NUM> may be coupled to the other side of the electromagnet unit <NUM>. The coil wiring unit <NUM> may be manufactured as a PCB. The coil wiring unit <NUM> may be provided in the form of a circular plate having a hollow portion therein and corresponding to the shape of the casing <NUM>.

The sensor unit <NUM> may be provided as a plurality of sensor units <NUM>. The sensor unit <NUM> has two opposite ends respectively coupled to the coil wiring unit <NUM> and the amplifier unit <NUM> so that the sensor unit <NUM> is positioned inside the electromagnet unit <NUM>.

Specifically, the sensor unit <NUM> may be positioned at a front side of a portion between the pair of electromagnets <NUM>. The sensor units <NUM> may be disposed at preset intervals.

The sensor unit <NUM> may be provided colocatedly with the suspended body supported by the electromagnet unit <NUM> and measure a displacement of the suspended body. An eddy-current displacement sensor may be used as the sensor unit <NUM>.

More specifically, the sensor unit <NUM> includes a sensor substrate <NUM>, a sensor coil <NUM>, protrusion bodies <NUM>, a center hole <NUM>, and edge holes <NUM>.

The sensor substrate <NUM> may be configured as a PCB and extend toward the amplifier unit <NUM> and the coil wiring unit <NUM>. In this case, the sensor substrate <NUM> may extend to be longer in length than the electromagnet <NUM>.

In addition, the sensor substrate <NUM> may be positioned between the electromagnets <NUM> inside the electromagnet unit <NUM> so that the sensor substrate <NUM> is disposed in parallel with a tangential direction at any point on an outer periphery of a central axis. The sensor substrate <NUM>, provided as described above, may measure well the displacement of the suspended body supported along the central axis by the electromagnet unit <NUM>.

The sensor coil <NUM> may be provided on the sensor substrate <NUM> and configured as an eddy-current sensor coil.

The protrusion bodies <NUM> may protrude from four corners of the sensor substrate <NUM> in a longitudinal direction of the sensor substrate <NUM>.

The protrusion bodies <NUM>, provided as described above, may be provided to be fitted into holes formed in the coil wiring unit <NUM> and the amplifier unit <NUM>.

The center hole <NUM> may be provided in the form of a hole at a center of the sensor substrate <NUM>. In this case, the center hole <NUM> may extend to have a predetermined length in the longitudinal direction of the sensor substrate <NUM>. The center hole <NUM> may be positioned at a center based on a width direction of the sensor substrate <NUM>.

The edge holes <NUM> may be formed at two opposite ends based on the longitudinal direction of the sensor substrate <NUM>. That is, the edge holes <NUM> may be positioned on the same line as the center hole <NUM>.

The support unit <NUM> may be coupled between the sensor unit <NUM> and the casing <NUM> and extend to have a length corresponding to the sensor unit <NUM>. Further, the support unit <NUM> may be disposed in a direction orthogonal to the sensor unit <NUM>.

More specifically, the support unit <NUM> includes a support body <NUM>, a center support protrusion body <NUM>, edge support protrusion bodies <NUM>, and a support coupling body <NUM>.

The support body <NUM> may define a body of the support unit <NUM> and extend toward the amplifier unit <NUM> and the coil wiring unit <NUM> so as to have a length corresponding to the sensor substrate <NUM>.

In addition, the support body <NUM> may be oriented in a direction orthogonal to the sensor substrate <NUM>, one side surface of the support body <NUM> may be fixed to the casing <NUM>, and the other side of the support body <NUM> may be fixed while supporting a rear central axis of the sensor substrate <NUM>.

The center support protrusion body <NUM> may be formed on the other side surface of the support body <NUM> and provided at a position corresponding to the center hole <NUM>. The center support protrusion body <NUM>, provided as described above, may be fitted into the center hole <NUM>.

The edge support protrusion bodies <NUM> may be formed on the other side surface of the support body <NUM> and provided at positions corresponding to the edge holes <NUM>. The edge support protrusion bodies <NUM>, provided as described above, may be fitted into the edge holes <NUM>.

The support unit <NUM>, provided as described above, may prevent the sensor unit <NUM> from being bent or deformed.

Specifically, because the sensor unit <NUM> is a PCB provided in the form of a thin plate, the sensor unit <NUM> may be bent or deformed when the casing <NUM> rotates at high speed, which makes it difficult to accurately measure the displacement of the suspended body.

However, according to the present invention, because the support unit <NUM> is provided to support a center vertical axis of the sensor unit <NUM>, it is possible to prevent the deformation of the sensor unit <NUM>.

The reinforcement unit <NUM> has two opposite ends coupled to the coil wiring unit <NUM> and the amplifier unit <NUM> and includes a vertical reinforcement body <NUM> and reinforcement coupling bodies <NUM>.

Two opposite ends of the vertical reinforcement body <NUM> may extend toward the coil wiring unit <NUM> and the amplifier unit <NUM>.

The reinforcement coupling bodies <NUM> are provided as a pair of reinforcement coupling bodies <NUM> provided at the two opposite ends of the vertical reinforcement body <NUM>. The pair of reinforcement coupling bodies <NUM> are respectively coupled to the coil wiring unit <NUM> and the amplifier unit <NUM>.

As described above, according to the magnetic bearing <NUM> having the colocated eddy-current displacement sensor according to the first embodiment, the casing <NUM>, the coil wiring unit <NUM>, and the amplifier unit <NUM> are primarily coupled by the vertical frames <NUM> and the horizontal frames <NUM>, and the coil wiring unit <NUM> and the amplifier unit <NUM> are secondarily coupled by the reinforcement units <NUM>, which makes it possible to improve the durability.

In addition, the sensor unit <NUM> may also be positioned inside the electromagnet unit <NUM> by the above-mentioned coupling without deformation and accurately measure the displacement of the suspended body disposed colocatedly with the suspended body.

<FIG> is a perspective view illustrating an amplifier unit of a magnetic bearing having a colocated eddy-current displacement sensor according to a second embodiment of the present invention, and <FIG> is a perspective view illustrating a coil wiring unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the second embodiment of the present invention.

<FIG> is a perspective view illustrating a state in which the amplifier unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the second embodiment of the present invention is detached, <FIG> is an enlarged perspective view of a sensor unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the second embodiment of the present invention, and <FIG> is a perspective view of the sensor unit according to the second embodiment of the present invention.

Referring to <FIG>, a magnetic bearing <NUM> having a colocated eddy-current displacement sensor according to a second embodiment includes an electromagnet unit <NUM>, an amplifier unit <NUM>, a coil wiring unit <NUM>, sensor units <NUM>, and support units <NUM>.

The electromagnet unit <NUM> includes a casing <NUM>, electromagnets <NUM>, and column parts <NUM>.

The column parts <NUM> may be provided between the casing <NUM> and the coil wiring unit <NUM>.

Specifically, the column parts <NUM> may be provided at preset intervals along a periphery of the other side surface of the casing <NUM>.

The column parts <NUM>, provided as described above, may fixedly couple the casing <NUM> and the coil wiring unit <NUM>.

Although not illustrated, the column parts <NUM> may be further provided between the casing <NUM> and the amplifier unit <NUM>.

<FIG> is a perspective view illustrating a state in which an amplifier unit of a magnetic bearing having a colocated eddy-current displacement sensor according to a third embodiment of the present invention is detached, and <FIG> is a perspective view illustrating a coil wiring unit of the magnetic bearing having the colocated eddy-current displacement sensor according to the third embodiment of the present invention.

<FIG> is an enlarged perspective view illustrating a sensor unit magnetic bearing having the colocated eddy-current displacement sensor according to the third embodiment of the present invention, and <FIG> is a perspective view of the sensor unit according to the third embodiment of the present invention.

Referring to <FIG>, a magnetic bearing <NUM> having a colocated eddy-current displacement sensor according to a third embodiment includes an electromagnet unit <NUM>, an amplifier unit <NUM>, a coil wiring unit <NUM>, sensor units <NUM>, and coupling units <NUM>.

More specifically, the sensor unit <NUM> includes a sensor substrate <NUM>, a sensor coil <NUM>, and fitting holes <NUM>.

The fitting holes <NUM> may be formed at four corners of the sensor substrate <NUM>. The fitting hole <NUM> may be provided in the form of a hole. In this case, the fitting hole <NUM> may extend to be longer in the width direction of the sensor substrate <NUM> than in the longitudinal direction of the sensor substrate <NUM>.

The coupling unit <NUM> may be configured to further couple and fix the sensor unit to the horizontal frame <NUM> and include a coupling body <NUM>, fitting bodies <NUM>, and fixing bodies <NUM>.

The coupling body <NUM> may define a body of the coupling unit <NUM> and extend in a direction parallel to the sensor substrate <NUM>.

The fitting bodies <NUM> may extend toward the fitting holes <NUM> disposed adjacent to the two opposite ends of the coupling body <NUM>. The fitting body <NUM>, provided as described above, may be fitted into the fitting holes <NUM>.

The fixing bodies <NUM> may extend to be coupled to the horizontal frames <NUM> disposed adjacent to the two opposite ends of the coupling body <NUM>.

The fixing bodies <NUM> are fitted into the fitting holes <NUM> formed at the four corners of the sensor unit <NUM>, such that the sensor unit <NUM> may be stably supported and fixed.

More specifically, the fixing bodies <NUM> may be coupled to lower sides of the horizontal frames <NUM>, and the coil wiring unit <NUM> or the amplifier unit <NUM> may be coupled to upper sides of the horizontal frames <NUM>.

The coupling units <NUM>, provided as described above, may prevent the sensor unit <NUM> from being bent or deformed.

However, according to the present invention, because the coupling unit <NUM> is provided to support the four corners of the sensor unit <NUM>, it is possible to prevent the deformation of the sensor unit <NUM>.

According to the present invention configured as described above, the sensor unit <NUM> is disposed inside the electromagnet unit <NUM>, which makes it possible to reduce a sensor installation space and manufacturing costs and solve a problem of sensor noise.

In addition, according to the present invention, the sensor unit <NUM> is assembled by fitting, which makes it easy to assemble and disassemble the sensor unit <NUM>.

In addition, according to the present invention, the sensor unit <NUM> is positioned on the same central axis as the suspended body, which makes it possible to improve accuracy in measuring the displacement.

It will be appreciated that the embodiments of the present invention have been described above for purposes of illustration, and those skilled in the art may understand that the present invention may be easily modified in other specific forms without changing the technical spirit or the essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and do not limit the present invention. For example, each component described as a single type may be carried out in a distributed manner. Likewise, components described as a distributed type can be carried out in a combined type.

Claim 1:
A magnetic bearing (<NUM>) having a coaxial eddy-current displacement sensor, the magnetic bearing comprising:
an electromagnet unit (<NUM>, <NUM>, <NUM>) including a circular casing (<NUM>) having a hollow portion therein, and a plurality of electromagnets (<NUM>) disposed along an inner periphery of the casing;
an amplifier unit (<NUM>) coupled to one side of the electromagnet unit;
a coil wiring unit (<NUM>) coupled to the other side of the electromagnet unit; and
a plurality of sensor units (<NUM>) disposed along an inner periphery of the electromagnet unit and each having two opposite ends respectively coupled to the coil wiring unit (<NUM>) and the amplifier unit (<NUM>), the plurality of sensor units (<NUM>) being provided between the coil wiring unit (<NUM>) and the amplifier unit(<NUM>), wherein the sensor unit (<NUM>) is disposed coaxially with a suspended body supported by the electromagnet unit and configured to measure a displacement of the suspended body.