KR101363558B1 - Apparatus of non-contact mass measurement - Google Patents

Abstract

Disclosed is a contactless mass measuring device for measuring current values consumed when the displacement of a levitation member is corrected depending on the load applied in a magnetic levitated contactless state and converting the current values to mass. The present invention comprises: the levitation member having a cross-shaped cross section; a pair of permanent magnets of which one is installed on the top of a vertical part and the other is separated therefrom so that the levitation member can be levitated; horizontal electromagnets for radially supplying suction force from the axial center of the vertical part to guide the levitation member; an axis sensor for detecting whether or not the center of the vertical part matches with the center of the horizontal electromagnets; and ring-shaped vertical electromagnets for supplying the suction force in the vertical direction of a horizontal part to control the vertical position of the levitation member; a height sensor for detecting whether or not the horizontal part is positioned at the center between the vertical electromagnets; a control part connected to the height sensor to output the current to the vertical electromagnets so that the horizontal part can be returned to the original position when not positioned at the center between the vertical electromagnets; and a calculation part for measuring the current values outputted from the control part through a current sensor and converting the current values to the mass of a sample. [Reference numerals] (100) Levitation member; (201,202) Permanent magnets; (300) Holding member; (400) Horizontal electromagnets; (500) Vertical electromagnets; (910) Axis sensor; (920) Height sensor; (930) Control part; (940) Calculation part; (950) Power supply unit

Description

Apparatus of non-contact mass measurement

The present invention relates to a non-contact mass measurement device, and more particularly to a non-contact mass measurement device for converting the mass by measuring the current value required to compensate for the displacement of the floating member according to the load applied in the magnetic injuries non-contact state will be.

In general, load measurement was generally performed using a strain gauge. Load measurement using a strain gauge is a method of measuring the strain of the strain gauge that is deformed to correspond to the deformation of the elastic body when a load is applied. This initial load measurement method is not only accurate by the contact method, but also had a problem that the characteristics are changed after several measurements.

In order to solve the problem of the contact load measuring method by the strain gauge, a non-contact load measuring device has been proposed. The non-contact load measuring method is a method of measuring the displacement of the elastic body in a non-contact manner using an electromagnetic induction phenomenon without measuring the deformation amount of the strain gauge coupled to the elastic body.

Although the non-contact load measuring method can have a higher precision than the conventional strain gauge method and can maintain the same characteristics even for a long time, the precision of the load measuring device is still dependent on the sensitivity of the elastic body. .

The present invention implements a means for guiding so that the floating member does not tilt, thereby minimizing distortion due to nonlinearity generated while the floating member is rotated or tilted in the process of measuring the mass of the sample, thereby allowing more accurate mass measurement. The object of the present invention is to provide a mass measuring device.

Non-contact mass measurement apparatus according to an embodiment of the present invention for achieving the above object includes a vertical portion of the cylindrical shape, a horizontal portion protruding in a circular shape so as to be perpendicular to the outside of the vertical portion, a floating member made of a ferromagnetic material, A pair of permanent magnets spaced apart from the upper end and the upper part of the vertical part to provide a suction force in the axial direction to compensate the self-weight of the floating member, and the floating to allow the sample to be placed for mass measurement A mounting member formed at an upper end or a lower end of the member, a horizontal electromagnet disposed at an upper side and a lower side so as to surround the periphery of the vertical part, and providing a suction force radially with respect to the center of the shaft to guide the floating member; An axis detecting sensor for detecting whether a center coincides with a center of the horizontal electromagnet, and an upper portion of the horizontal part An annular vertical electromagnet disposed side by side in the upper part and providing suction in the vertical direction to adjust the position of the floating member in the vertical direction, and a height sensing sensor for detecting whether the horizontal part is located at the center between the vertical electromagnets; And a controller connected to the height sensor and outputting a current to the vertical electromagnet so as to return to a home position when the horizontal portion is not located at the center between the vertical electromagnets, and a current value output from the controller through a current sensor. It computes and includes the calculating part which converts the mass of a sample.

According to an embodiment of the present invention, the horizontal electromagnet includes a hollow guide ring, a core extending radially from the inner surface of the guide ring, radially disposed, and a coil wound around the core.

According to an embodiment of the present invention, the vertical electromagnet includes a ring member having a cross-section having a 'C' shape at one side thereof, and a coil wound inside the ring member, and the openings face each other. do.

According to one embodiment of the invention, the floating member is formed in the center of the vertical portion of the horizontal portion has a cross-shaped cross section.

According to an embodiment of the present invention, the floating member and the electromagnet further include a non-magnetic separator corresponding to the shape of the floating member and having a volume larger than that of the floating member so as to form a predetermined gap with the floating member. .

According to the present invention, since the mass is measured without mechanical contact in a limited space in a non-contact manner by magnetic levitation, vibration can be minimized and precise mass measurement is possible.

In addition, by implementing a means for guiding so that the floating member is not inclined, it is possible to minimize the distortion caused by non-linearity caused by the rotation or inclination of the floating member in the process of measuring the mass of the sample, it is possible to measure the mass more accurately.

In addition, a separator made of a nonmagnetic material is formed between the floating member and the electromagnet to spatially separate the sample and the electromagnet so that mass measurement can be performed under objective and uniform environmental conditions.

1 is a block diagram of a non-contact mass measurement device according to an embodiment of the present invention;
2 is a perspective view of a non-contact mass measuring device according to an embodiment of the present invention;
3 is a cross-sectional view of a non-contact mass measuring device according to another embodiment of the present invention;
4 is a cross-sectional view of a non-contact mass measurement device mounted with a sample according to another embodiment of the present invention.

The present invention will now be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same components, and repeated descriptions and detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

1 is a block diagram of a non-contact mass measurement device according to an embodiment of the present invention, Figure 2 is a perspective view of a non-contact mass measurement device according to an embodiment of the present invention, Figure 3 according to another embodiment of the present invention 4 is a cross-sectional view of a non-contact mass measurement device, and FIG. 4 is a cross-sectional view of a non-contact mass measurement device on which a sample according to another embodiment of the present invention is placed.

1 to 4, the non-contact mass measuring apparatus according to an embodiment of the present invention is a horizontal portion protruding in a circular shape on the outside so as to be perpendicular to the vertical portion 110 of the cylindrical shape, and the vertical portion 110 The vertical portion 110 including a portion 120, the floating member 100 made of a ferromagnetic material, and a suction force for compensating for the weight of the floating member 100 in the axial direction to the floating member 100 is floating. A pair of permanent magnets 201 and 202 spaced apart from the upper end and the upper part thereof, and the mounting member 300 formed at the upper or lower end of the floating member 100 so that the sample 10 is mounted for mass measurement. And a horizontal electromagnet 400 disposed at the top and bottom to surround the periphery of the vertical part 110 to provide the suction force radially with respect to the axial center to guide the floating member 100. The center of the 110 is the horizontal electromagnet 400 Axial sensor 910 for detecting whether or not coinciding with the shim, and arranged side by side on the upper and lower portions of the horizontal portion 120, providing a suction force in the vertical direction to the vertical position of the floating member 100 An annular vertical electromagnet 500 for controlling the height, the height sensor 920 for detecting whether the horizontal portion 120 is located in the center between the vertical electromagnet 500 and the height sensor 920 Is connected to, when the horizontal portion 120 is not located in the center between the vertical electromagnet 500, the control unit 930 for outputting a current to the vertical electromagnet 500 to return to the original position, and through the current sensor And a calculator 940 for measuring a current value output from the controller 930 and converting the mass of the sample 10.

First, the floating member 100 is made of a ferromagnetic material, and includes a vertical portion 110 of a circumferential shape, and a horizontal portion 120 protruding in a circle to be perpendicular to the outside of the vertical portion 110. Accordingly, the floating member 100 may have a 'T' shape or a '十' shape, and may be non-contacted with the horizontal electromagnet 400 and the vertical electromagnet 500 by magnetic levitation by the permanent magnets 201 and 202. State can be maintained. In order to measure the mass of the sample 10, the sample 10 is suspended from the bottom of the floating member 100, or when the sample 10 is placed on the top of the floating member 100, the weight of the sample 10 As a result, the floating member 100 descends and displacement occurs in the vertical direction.

The permanent magnets 201 and 202 are spaced apart from the upper end and the upper portion of the vertical part 110 so that the floating member 100 floats by providing a suction force for compensating the weight of the floating member 100 in the axial direction.

The permanent magnet 201 is fixed to the top of the floating member 100, the other permanent magnet 202 may be fixed on the frame 700 provided separately. The frame 700 may include the permanent magnet 202, a horizontal electromagnet 400, a vertical electromagnet 500, and sensors 910 and 920, and the floating member 100 may be accommodated in an internal space. Can be. On the other hand, the permanent magnets 201 and 202 may generate a repulsive force as well as a suction force to compensate for the weight of the floating member 100. When using the repulsive force as described above, the permanent magnet may be disposed spaced apart from the lower end of the floating member 100, the lower portion.

The mounting member 300 is formed at the top or bottom of the floating member 100 so that the sample 10 is mounted for mass measurement. That is, the shape of the mounting member 300 may be determined according to where the sample 10 is mounted on the floating member 100. For example, the mounting member 300 may include a wire 310 connected to the lower end of the floating member 100 and a holder 320 fixed to an end of the wire 310, the holder 320 The mass 10 can be measured by placing the sample 10 thereon. In such a case, the permanent magnets 201 and 202 should be able to compensate not only the floating member 100 but also the weight of the mounting member 300.

The horizontal electromagnet 400 may take the form of a ring, and is disposed at the top and the bottom to surround the periphery of the vertical part 110, and provides a suction force radially with respect to the center of the shaft so that the floating member 100 does not tilt. Support it. Therefore, the surface of the vertical portion 110 and the inner side of the horizontal electromagnet 400 facing the vertical portion 110 may form different poles to generate suction. By the action of the horizontal electromagnet 400, the floating member 100 can maintain the injured state without shaking back and forth, left and right, and stable lifting operation can be made. Meanwhile, the horizontal electromagnet 400 may generate a repulsive force as well as a suction force to guide the floating member 100 not to shake.

The axis detecting sensor 910 senses the inclination of the floating member 100 in a manner of detecting whether the center of the vertical portion 110 coincides with the center of the horizontal electromagnet 400. Therefore, when the axis detecting sensor 910 detects a misalignment between the center of the vertical portion 110 and the center of the horizontal electromagnet 400, the horizontal electromagnet 400 is controlled by the controller 930 to correct the center. By outputting a current to the coil of the control to increase the suction force in the inclined opposite direction, it can be controlled to match the center of the vertical portion 110 and the center of the horizontal electromagnet 400. As described above, when the centers of the vertical parts 110 and the horizontal electromagnets 400 coincide with each other, the distortion due to nonlinearity generated while the floating member 100 is rotated or tilted in the process of measuring the mass of the sample 10 is minimized. can do.

The vertical electromagnet 500 is disposed in parallel with the upper and lower portions of the horizontal portion 120, and provides a suction force in the vertical direction to adjust the position of the vertical member of the floating member 100. By the action of the vertical electromagnet 500, the floating member 100 can be elevated without shaking in the injured state. That is, the surface of the horizontal portion 120 and one surface of the vertical electromagnet 500 facing the horizontal portion 120 form a different pole to generate a suction force. Meanwhile, the vertical electromagnet 500 may raise and lower the floating member 100 by generating a repulsive force as well as a suction force.

The height sensor 920 detects whether the horizontal portion 120 is located at the center between the vertical electromagnets 500. That is, in order to suspend the sample 10 at the lower end of the floating member 100 or to place the sample 10 at the upper end for the measurement of the mass of the sample 10, the floating member 100 is caused by the weight of the sample 10. When is falling, this displacement is detected.

The control unit 930 is connected to the height sensor 920, when the horizontal portion 120 is not located in the center between the vertical electromagnets 500, the current to the vertical electromagnet 500 to return to the original position Output When the sample 10 is placed on the holder 320 connected to the floating member 100, the floating member 100 descends, and as a result, the horizontal portion 120 descends from the center between the vertical electromagnets 500. do. The control unit 930 measures the displacement of the floating member 100 to output a current to the coil of the vertical electromagnet 500 and to increase the suction force feedback control for returning the horizontal portion 120 to its original position (feedback control) ). For reference, the controller 930 may be connected to a separate power supply means 950 to output a current to the coil, the power supply means may be an external power source.

The calculator 940 measures a current value output during the feedback control from the controller 930 through a current sensor and converts the mass of the sample 10. Since the current output from the coil of the vertical electromagnet 500 through the controller 930 is directly related to the mass of the sample 10, the mass of the sample 10 may be converted by measuring the current required by the current sensor. Can be. As described above, since the current flowing through the coil of the vertical electromagnet 500 is directly related to the mass of the sample 10, the accuracy of the mass measurement may be determined by the current sensor measuring the current of the coil. Therefore, the current sensor needs to have high precision, and a hole probe or the like can be used. In addition, a current amplifier may be further disposed to improve measurement accuracy of the current sensor.

Referring to the mass measurement process using the height sensor 920, the controller 930 and the calculator 940 as follows. When measuring the mass of the sample 10, if the floating member 100 is lowered in the axial direction by the mass of the sample 10, the height sensor 920 detects this, the control unit 930 is a floating member ( Output current to the coil of the vertical electromagnet 500 so that 100 returns to its original position, and measures the current value required to raise the floating member 100 through the current sensor. In the calculator 940, the mass of the sample 10 may be measured by converting mass into a current value measured by the current sensor.

According to an embodiment of the present invention, the horizontal electromagnet 400 is a hollow guide ring 410, and protrudes inward from the inner surface of the guide ring 410, the core 420 disposed radially And a coil 430 wound around the core 420. As described above, the core 420 and the coil 430 disposed radially with respect to the vertical part 110 flow current so as to generate suction force radially with respect to the vertical part 110, and the suction force supplied evenly in the radial direction. By the vertical portion 110 maintains the floating state while maintaining a straight line, it is possible to guide the lifting of the horizontal portion 120.

According to an embodiment of the present disclosure, the vertical electromagnet 500 has a ring member 510 having a cross-section of a 'c' shape with one side opened, and a coil 520 wound inside the ring member 510. ) And the openings face each other. The ring member 510 has a container-shaped cross section, such as 'U' and 'ㄷ', and forms an opening at one side. At this time, the ring member 510 itself serves as a core. The polarity of the vertical electromagnet 500 may vary according to the current direction of the coil 520 wound around the ring member 510. In this case, the vertical electromagnet 500 may generate suction with respect to the horizontal portion 120 which is adjacent to each other by forming the opposite poles facing each other.

According to one embodiment of the present invention, the floating member 100 has the horizontal portion 120 is formed in the center of the vertical portion 110 has a cross-shaped cross section. As described above, when the cross section of the floating member 100 is cross-shaped, the upper and lower ends of the floating member 100 are guided by the horizontal electromagnet 400 so that it is easy to maintain a straight line and more sensitive to the inclination in the axial direction. It can be detected.

According to an embodiment of the present invention, between the floating member 100 and the electromagnets 400 and 500 corresponds to the outer shape of the floating member 100, and the floating member 100 to form a predetermined interval with the floating member 100 ( It further comprises a non-magnetic separator 600 having a volume greater than 100). As the separation membrane 600 is disposed, spatial separation between the space in which the sample 10 is located and the electromagnets 400 and 500 may be more stable, and mass measurement may be performed under a constant state condition. In addition, to ensure a more objective and accurate mass measurement, the inside of the separator 600 may be maintained in a vacuum state, a constant temperature or a humidity system may be constructed, and the mass may be filled in a state in which a separate gas is filled. It can be measured.

According to the present invention as described above, since the mass is measured without mechanical contact in a limited space in a non-contact manner by magnetic levitation, it is possible to minimize vibration and to measure the mass accurately. In addition, by implementing a means for guiding so that the floating member 100 is not inclined, it is possible to minimize the distortion caused by non-linearity generated while the floating member 100 is rotated or tilted in the process of measuring the mass of the sample 10 The advantage is that more accurate mass measurements can be made.

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical spirit of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by the embodiments and the accompanying drawings. . The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

10: sample
100: floating member
110: vertical part
120: horizontal section
201,202: Permanent magnet
300: mounting member
400: horizontal electromagnet
410: guide ring
420: Core
430 coil
500: vertical electromagnet
510: ring member
520: coil
600: separator
910: Axis detection sensor
920: height sensor
930: control unit
940: calculating unit

Claims (5)

A floating member formed of a ferromagnetic material, the vertical portion having a circumferential shape and a horizontal portion protruding in a circular shape so as to be perpendicular to the outside of the vertical portion;
A pair of permanent magnets spaced apart from an upper end of the vertical portion and an upper portion thereof to provide a suction force for compensating a weight of the floating member in an axial direction so that the floating member floats;
Mounting member formed on the top or bottom of the floating member so that the sample is mounted for mass measurement;
A horizontal electromagnet disposed at an upper portion and a lower portion so as to surround a periphery of the vertical portion, the horizontal electromagnet guiding the floating member by providing a suction force radially with respect to an axial center;
An axis detecting sensor for detecting whether a center of the vertical portion coincides with a center of the horizontal electromagnet;
An annular vertical electromagnet disposed side by side at the top and the bottom of the horizontal part and providing a suction force in an up and down direction to adjust a position in the vertical direction of the floating member;
A height sensor for detecting whether the horizontal part is located at the center between the vertical electromagnets;
A control unit connected to the height sensor and outputting a current to the vertical electromagnet so as to return to the original position when the horizontal portion is not located at the center between the vertical electromagnets;
Non-contact mass measurement apparatus comprising a; measuring unit for measuring the current value output from the control unit through a current sensor, and converting the mass of the sample. The method of claim 1, wherein the horizontal electromagnet is
Hollow guide ring;
A core protruding inward from the inner side of the guide ring and disposed radially;
The coil wound around the core; Non-contact mass measurement apparatus comprising a. The method of claim 1, wherein the vertical electromagnet is
A ring member having a cross-section of a 'c' shape having one side opened;
And a coil wound around the inside of the ring member, wherein the openings are arranged to face each other. The method of claim 1,
The floating member is a non-contact mass measuring device, characterized in that the horizontal portion is formed in the center of the vertical portion has a cross-shaped cross section. The method of claim 1,
Non-contact mass measuring device further comprises a non-magnetic separator between the floating member and the electromagnet corresponding to the shape of the floating member and having a volume larger than that of the floating member to form a predetermined gap with the floating member.

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