CN117760300A - Eddy current radial sensor, magnetic suspension bearing assembly and compressor - Google Patents

Abstract

The utility model provides an eddy current radial sensor, a magnetic suspension bearing assembly and a compressor. The eddy current radial sensor comprises a plurality of block structures which are sequentially distributed along the circumferential direction, wherein the block structures are spliced to form an annular sensor shell (1), the sensor shell (1) comprises an inner annular wall (3) and an outer annular wall (4), an installation groove (2) is formed between the inner annular wall (3) and the outer annular wall (4), a first radial detection hole (5) is formed in the inner annular wall (3) along the radial direction, and a radial probe (6) is arranged in the first radial detection hole (5). According to the eddy current radial sensor, the axial size of the sensor can be reduced, the space is saved, and the installation structure is simplified.

Description

Eddy current radial sensor, magnetic suspension bearing assembly and compressor

Technical Field

The utility model relates to the technical field of magnetic suspension, in particular to an eddy current radial sensor, a magnetic suspension bearing assembly and a compressor.

Background

The magnetic suspension bearing is to suspend the rotor in the air by electromagnetic force, so that the rotor and the stator have no mechanical contact. To achieve a stable suspension of the shaft in space, the position of the shaft in space must be detected. The detection of the axial displacement and the radial displacement of the rotor is the basis for controlling the whole system.

When the magnetic suspension bearing works, the rotating shaft is suspended in the air through electromagnetic force, so that the mechanical contact between the rotating shaft and the stator of the magnetic bearing is avoided. Compared with mechanical bearings, the magnetic suspension bearing has the advantages of no mechanical abrasion, no need of lubrication, long service life, high rotating speed, strong reliability and the like. Therefore, the magnetic suspension bearing is widely used in the industrial manufacturing fields of high-speed rotation such as flywheel energy storage, molecular pumps, compressors, aerospace and the like. In order to enable the rotating shaft to continuously and stably rotate in operation, the axis track of the rotating shaft needs to be monitored by using a displacement sensor.

In general, the whole structure of the displacement sensor component of the radial magnetic bearing is mostly disc-shaped, sensors are respectively arranged on the periphery of the disc, a PCB circuit board is placed on the end face, colloid is filled into the end face for sealing, and then the end face is arranged on the end face of the cover plate of the radial magnetic bearing.

In the Chinese patent with the publication number of CN204240938U, the utility model name of the electric vortex sensor discloses an electric vortex sensor, a sensor part adopts an integral disc structure, large-area colloid is filled in the sensor for sealing and curing, the structure is large in size and is arranged on the end face of a radial magnetic bearing shell, the installation position is limited, and only one part of the part is damaged, so that the whole part needs to be replaced, and the cost is increased. And the structure is more complex to install, the axial length of the rotating shaft can be increased, and the volume of the whole device is increased.

Disclosure of Invention

The utility model mainly aims to provide an eddy current radial sensor, a magnetic suspension bearing assembly and a compressor, which can reduce the axial size of the sensor, save space and simplify the installation structure.

In order to achieve the above object, according to an aspect of the present utility model, there is provided an eddy current radial sensor, including a plurality of block structures sequentially arranged in a circumferential direction, the plurality of block structures being spliced to form an annular sensor housing, the sensor housing including an inner annular wall and an outer annular wall, a mounting groove being formed between the inner annular wall and the outer annular wall, a first radial detection hole being provided in the inner annular wall in a radial direction, and a radial probe being mounted in the first radial detection hole.

Further, a plurality of first radial detection holes are uniformly formed in the inner annular wall of the sensor housing along the circumferential direction.

Further, central axes of two adjacent first radial detection holes are perpendicular to each other.

Further, the outer annular wall is provided with second radial detection holes, the second radial detection holes and the first radial detection holes are arranged in one-to-one correspondence, and the corresponding second radial detection holes and the first radial detection holes are coaxial.

Further, the block structures are identical.

Further, the outer annular wall of the block structure is provided with a lateral through groove, and the lateral through groove penetrates through the outer annular wall along the radial direction of the sensor shell.

Further, the mounting groove is an annular groove, and two ends of the annular groove of the block structure are respectively provided with a stop wall.

Further, the eddy current radial sensor also comprises a PCB signal board, and the radial probe and the PCB signal board are filled into the sensor shell and then are encapsulated and fixed.

According to another aspect of the utility model, a magnetic suspension bearing assembly is provided, which comprises a main shaft, and the magnetic suspension bearing assembly further comprises the eddy current radial sensor, wherein the eddy current radial sensor is sleeved on the main shaft.

Further, the main shaft comprises a middle shaft section and annular protruding shafts positioned at two ends of the middle shaft section, the eddy current radial sensor is arranged on the middle shaft section, the detection end of the radial probe faces the peripheral wall of the middle shaft section, and the central axis of the radial probe is intersected with and perpendicular to the central axis of the middle shaft section.

Further, the number of the eddy current radial sensors is two, and the two eddy current radial sensors are arranged at intervals along the axial direction of the main shaft.

According to another aspect of the present utility model, there is provided a compressor comprising the above-described eddy current radial sensor or the above-described magnetic bearing assembly.

By applying the technical scheme of the utility model, the eddy current radial sensor comprises a plurality of block structures which are sequentially distributed along the circumferential direction, the block structures are spliced to form an annular sensor shell, the sensor shell comprises an inner annular wall and an outer annular wall, a mounting groove is formed between the inner annular wall and the outer annular wall, a first radial detection hole is formed in the inner annular wall along the radial direction, and a radial probe is arranged in the first radial detection hole. This electric vortex radial sensor adopts split type structure, can optimize radial sensor's assembly structure, improve radial sensor's assembly efficiency, save assembly time, because radial sensor adopts split type structure, and only be used for carrying out radial detection, consequently, can reduce radial sensor's axial dimensions, radial sensor's the installation degree of difficulty is reduced, and can make the structure compacter, the technology is simpler, radial sensor's installation and dismantlement of being convenient for, because radial sensor includes a plurality of blocking structures of arranging in proper order along the circumference, therefore blocking structure can assemble the combination from radial direction, can assemble in any position that is suitable for the assembly, not receive the restriction of assembly structure, can conveniently carry out radial sensor's installation allotment more, can effectively improve radial detection's precision and sensitivity.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

FIG. 1 shows a schematic perspective view of a split structure of an eddy current radial sensor according to an embodiment of the utility model;

FIG. 2 shows a schematic structural diagram of an eddy current radial sensor according to an embodiment of the utility model;

FIG. 3 shows a schematic diagram of the detection relationship of an axial sensor and a spindle according to an embodiment of the present utility model; and

fig. 4 shows a schematic view of the installation position structure of the axial sensor and the main shaft according to the embodiment of the present utility model.

Wherein the above figures include the following reference numerals:

1. a sensor housing; 2. a mounting groove; 3. an inner annular wall; 4. an outer annular wall; 5. a first radial probe hole; 6. a radial probe; 7. a lateral through groove; 8. a stop wall; 9. a second radial probe hole; 10. an annular protruding shaft; 11. a main shaft; 12. a middle shaft section; 13. a front bearing; 14. and a rear bearing.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The utility model will be described in detail below with reference to the drawings in connection with embodiments.

Referring to fig. 1 to 4 in combination, according to an embodiment of the present utility model, the eddy current radial sensor includes a plurality of block structures sequentially arranged in a circumferential direction, the plurality of block structures are spliced to form an annular sensor housing 1, the sensor housing 1 includes an inner annular wall 3 and an outer annular wall 4, a mounting groove 2 is formed between the inner annular wall 3 and the outer annular wall 4, a first radial detection hole 5 is radially provided on the inner annular wall 3, and a radial probe 6 is mounted in the first radial detection hole 5.

The eddy current radial sensor adopts a split structure, can optimize the assembly structure of the radial sensor, improves the assembly efficiency of the radial sensor, saves the assembly time, splits the radial sensor for the magnetic suspension bearing into at least two parts, respectively installs the at least two parts at the specific position of the required detection main shaft 11, and then splices, thus the assembly structure is simple in structure process, flexible in installation, space-saving and convenient for disassembly and assembly.

Because radial sensor adopts split type structure, and only be used for carrying out radial detection, consequently can reduce radial sensor's whole axial dimension, reduce radial sensor's the installation degree of difficulty, and can make the structure compacter, the technology is simpler, radial sensor's installation and dismantlement of being convenient for, because radial sensor includes a plurality of blocking structures of arranging in proper order along the circumference, therefore blocking structure can assemble the combination from radial direction, can assemble in any position that is suitable for the assembly, not receive the restriction of assembly structure, can conveniently carry out radial sensor's installation allotment more, can effectively improve radial detection's precision and sensitivity.

In the present embodiment, a plurality means two or more.

When the assembly of the eddy current radial sensor is carried out, the sensor shell 1 can be split into a plurality of block structures, then the block structures are respectively arranged at the radial detection positions of the main shaft 11 according to the assembly requirement, and then the split structures are spliced. The radial gap between the radial sensor and the radial detection position of the main shaft 11 can be adjusted in the assembly process of the block structure of the radial sensor, so that the radial gap between the radial sensor and the radial detection position of the main shaft 11 is within the design range, and the detection precision and sensitivity of the radial sensor are improved.

In a magnetic levitation rotor system, to achieve stable levitation of the shaft in space, sensors are the basis for controlling the whole system. The sensor in the prior art is of a whole disc structure and is matched and assembled with parts such as a bearing during assembly, but the shaft is provided with a plurality of shaft shoulders with different sizes, when the compressor is assembled, the shaft is installed firstly, then other parts are installed, finally the sensor matched with the bearing is installed, and the sensor can only be installed on the shaft shoulder at the outermost end of the shaft. In order to meet different requirements of the compressor, the utility model provides that the sensor adopts a splicing structure to realize the installation of different shaft neck positions on the main shaft 11, the sensor can be independently installed, and the problem that the whole compressor part is required to be disassembled and replaced when the sensor is damaged can be avoided.

The sensor of prior art is whole discoid structure, and radial sensor and axial sensor are integrative, and sensor axial size is great moreover, in the use, because radial sensor and axial sensor's distance is too close, the magnetic circuit takes place the interference problem easily, influences axial distance and radial distance detection's reliability. The radial detection structure and the axial detection structure of the split type sensor are separated, the radial sensor only detects the radial displacement of the main shaft 11, the axial sensor only detects the axial displacement of the main shaft 11, and the split type sensor is independent and separated, and can not be interfered by signals of the radial sensor and the axial detection structure. And when the radial or axial sensor fails, only the failed component needs to be replaced, so that the maintenance cost can be reduced.

The existing radial and axial integrated sensor is split into two sensors, namely the original large-size sensor is split into two small-size sensors, so that the size of each sensor can be reduced, interference between the axial sensor and the radial sensor can be avoided, and the detection precision and reliability of the sensor are ensured.

In one embodiment, a plurality of first radial detection holes 5 are uniformly provided on the inner annular wall 3 of the sensor housing 1 in the circumferential direction.

In this embodiment, the plurality of first radial detection holes 5 are uniformly disposed on the inner annular wall 3 of the sensor housing 1 in the circumferential direction, so that the radial play displacement of the main shaft 11 can be detected from a plurality of positions in the circumferential direction of the main shaft 11, and the radial displacement detection of the main shaft 11 is more accurate.

In one embodiment, the central axes of two adjacent first radial detection holes 5 are perpendicular to each other.

In this embodiment, the number of the first radial detection holes 5 is four, and the detection ends of the radial probes 6 are oriented perpendicularly to the axial direction of the inner hole of the sensor housing 1, respectively, and the central axes of the adjacent radial probes 6 intersect and form an included angle of 90 degrees, so that the radial sensor can accurately detect the radial play displacement of the main shaft 11 in two mutually orthogonal directions.

In one embodiment, each block structure is identical, batch production can be carried out on the block structure, applicability of the block structure is improved, assembly difficulty and processing cost of the block structure are reduced, and assembly efficiency is improved.

In one embodiment, the block structures are semicircular, and each block structure is provided with two first radial detection holes 5, and central axes of the two first radial detection holes 5 intersect and are perpendicular. The two semicircular block structures are symmetrically arranged on the main shaft 11, and four radial probes 6 are respectively arranged to detect radial movement displacement of the main shaft 11 during working, so that the movement displacement of the main shaft 11 can be accurately detected in the radial direction.

In one embodiment, the outer annular wall 4 is provided with second radial detection holes 9, the second radial detection holes 9 and the first radial detection holes 5 are arranged in a one-to-one correspondence, and the corresponding second radial detection holes 9 and the first radial detection holes 5 are coaxial.

In this embodiment, the second radial detection hole 9 is disposed corresponding to the first radial detection hole 5, and penetrates through the inner annular wall 3 and the outer annular wall 4 of the sensor housing 1, so that when the mounting hole of the radial probe 6 is machined, machining can be performed from the outer annular wall 4 of the sensor housing 1 to the inner annular wall 3, thereby reducing machining difficulty and improving machining efficiency. During installation, the radial probe 6 can be installed in the first radial probe hole 5 through the second radial probe hole 9, and the routing of the radial probe 6 can be located in the second radial probe hole 9, so that the routing of the radial probe 6 is convenient.

In one embodiment, the outer annular wall 4 of the segmented structure is provided with lateral through-grooves 7, the lateral through-grooves 7 penetrating the outer annular wall 4 in the radial direction of the sensor housing 1.

In this embodiment, the lateral through groove 7 is used for routing, so that electrical connection between the wires and the PCB signal board is facilitated, and routing is also facilitated.

In one embodiment, the mounting groove 2 is an annular groove, and two ends of the annular groove of the block structure are respectively provided with a stop wall 8.

In this embodiment, set up backstop wall 8 respectively at the both ends of the ring channel of blocking structure, can prevent when carrying out the casting glue that the ring channel of adjacent blocking structure from communicating, lead to sealing glue two adjacent blocking structures fixed connection together, can effectively guarantee the independence of each blocking structure. In addition, to solitary blocking structure, when carrying out the pouring sealant, also can utilize backstop wall 8, interior rampart 3, outer rampart 4 and mounting groove 2's diapire to cooperate, form the sealing space, be convenient for control the sealing volume when the pouring sealant, realize good encapsulation effect, and can reduce the sealing quantity.

In one embodiment, the eddy current radial sensor further comprises a PCB signal board, and the radial probe 6 and the PCB signal board are fixed in a potting mode after being installed in the sensor housing 1.

Radial probes 6 and PCB signal boards are arranged in the block structure, after assembly, the radial probes and the PCB signal boards are fixed in a filling and sealing mode, gaps in the sensor shell 1 can be fully filled through filling and sealing, and therefore the use reliability of the radial sensor is improved. And then the encapsulated multiple block structures are respectively arranged at radial detection positions of the main shaft 11 according to the assembly requirements of the compressor. The radial sensor is installed in a split mode, so that the installation difficulty of the radial sensor is reduced, the assembly efficiency of the magnetic suspension compressor is improved, the problem that the parts of the sensor are damaged and the whole compressor part is required to be disassembled and replaced can be avoided.

Referring to fig. 1 to 4 in combination, the magnetic suspension bearing assembly includes a main shaft 11, and the magnetic suspension bearing assembly further includes the above-mentioned eddy current radial sensor, and the eddy current radial sensor is sleeved on the main shaft 11.

In one embodiment, the main shaft 11 comprises a middle shaft section 12 and annular protruding shafts 10 positioned at two ends of the middle shaft section 12, the eddy current radial sensor is arranged on the middle shaft section 12, the detection end of the radial probe 6 faces to the outer peripheral wall of the middle shaft section 12, and the central axis of the radial probe 6 is intersected with and perpendicular to the central axis of the middle shaft section 12.

With the main shaft 11 in the present embodiment, when there are the intermediate shaft section 12 and the annular protruding shafts 10 provided at both ends of the intermediate shaft section 12, and the diameter of the annular protruding shafts 10 is larger than that of the intermediate shaft section 12, since the diameters of the annular protruding shafts 10 at both ends are larger than that of the intermediate shaft section 12, it is impossible to mount to the intermediate shaft section 12 if a conventional integral sensor is employed. The radial sensor provided by the embodiment of the utility model adopts a split structure, and can be respectively arranged at the radial detection position of the small-diameter intermediate shaft section 12 in the radial direction, then spliced, and the radial sensor is free from integral installation, flexible in installation and more convenient to assemble and disassemble.

In one embodiment, the number of eddy current radial sensors is two, and the two eddy current radial sensors are arranged at intervals along the axial direction of the main shaft 11.

In this embodiment, the two eddy current radial sensors are an eddy current radial sensor Ta and an eddy current radial sensor Tb, respectively, and the two eddy current radial sensors are disposed along the axial direction of the main shaft 11 at intervals, so that radial gaps at different axial positions of the main shaft 11 can be detected, and the accuracy and reliability of radial gap detection can be further improved.

Referring to fig. 4, a schematic diagram of the installation of the radial sensor on the main shaft is shown, in this embodiment, the magnetic suspension bearing assembly further includes a front bearing 13 and a rear bearing 14, and in the conventional assembly process of the whole machine, the integral sensor is assembled on the main shaft 11, and then other parts such as the front bearing 13 and the rear bearing 14 are assembled. The radial gap B between the front bearing 13, the rear bearing 14 and the main shaft 11 is usually much smaller than the gap a between a conventional radial sensor and the main shaft 11, the working principle of the sensor is mainly based on the eddy current effect, the sensor probe can generate an alternating magnetic field, when the main shaft approaches to the magnetic field generated by the radial probe, the magnetic field excited by the radial probe can change, so that the effective impedance of a coil on the radial probe is changed, and the movement displacement generated by the main shaft is obtained. Therefore, the smaller the distance between the radial sensor and the measured spindle, the higher the detection accuracy and sensitivity of the sensor. When the conventional radial sensor is assembled, the gap between the radial sensor and the main shaft is relatively fixed and cannot be changed, and when the detection precision and the sensitivity of the radial sensor are required to be calibrated, the whole part is required to be repeatedly disassembled and assembled, so that the complexity and the difficulty of the calibration of the detection precision and the sensitivity of the radial sensor are increased.

In the split radial sensor provided by the embodiment of the utility model, when the assembly of the whole machine is performed, first, parts such as a front bearing 13, a rear bearing 14 and the like are assembled on a main shaft 11, and then, two split eddy current radial sensors Ta and an eddy current radial sensor Tb are assembled on the main shaft 11, wherein the eddy current radial sensor Ta is positioned at the front end of the main shaft 11, the eddy current radial sensor Tb is positioned at the rear end of the main shaft 11, and at this time, the radial gaps between the eddy current radial sensor Ta, the eddy current radial sensor Tb and the main shaft 11 are A. According to the actual situation, the whole parts are not required to be disassembled and assembled, and only the radial gaps between the electric vortex radial sensor Ta and the electric vortex radial sensor Tb and the main shaft 11 are required to be adjusted, so that the sizes of the radial gaps are between A and B, the detection precision and the sensitivity of the electric vortex radial sensor Ta and the electric vortex radial sensor Tb can be calibrated, and the problem that the parts are repeatedly disassembled and assembled when the detection precision and the sensitivity of the conventional radial sensor are calibrated is solved.

According to an embodiment of the utility model, the compressor comprises an eddy current radial sensor as described above or a magnetic bearing assembly as described above.

The split type radial sensor provided by the embodiment of the utility model does not need integral installation, has a simple structure and process, is flexible to install and convenient to disassemble and assemble, can adjust the detection precision and sensitivity of the sensor, and greatly improves the running stability of the system.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the present application described herein may be implemented in sequences other than those illustrated or described herein.

The above is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (12)

1. The utility model provides an electric vortex radial sensor, its characterized in that, includes a plurality of blocking structures of arranging in proper order along circumference, a plurality of blocking structure concatenation forms annular sensor housing (1), sensor housing (1) are including interior rampart (3) and outer rampart (4), interior rampart (3) with form mounting groove (2) between outer rampart (4), radially be provided with first radial detection hole (5) on interior rampart (3), install radial probe (6) in first radial detection hole (5).

2. The eddy current radial sensor according to claim 1, characterized in that a plurality of the first radial detection holes (5) are uniformly provided on the inner annular wall (3) of the sensor housing (1) in the circumferential direction.

3. An eddy current radial sensor according to claim 2, wherein the central axes of two adjacent first radial probe holes (5) are perpendicular to each other.

4. The eddy current radial sensor according to claim 1, wherein a second radial detection hole (9) is formed in the outer annular wall (4), the second radial detection hole (9) and the first radial detection hole (5) are arranged in a one-to-one correspondence, and the corresponding second radial detection hole (9) and the first radial detection hole (5) are coaxial.

5. The electrical vortex radial sensor of claim 1 wherein each of the segmented structures is identical.

6. The eddy current radial sensor according to claim 1, characterized in that the outer annular wall (4) of the segmented structure is provided with lateral through grooves (7), the lateral through grooves (7) penetrating the outer annular wall (4) in the radial direction of the sensor housing (1).

7. The eddy current radial sensor according to claim 1, wherein the mounting groove (2) is an annular groove, and both ends of the annular groove of the block structure are respectively provided with a stop wall (8).

8. The eddy current radial sensor according to claim 7, further comprising a PCB signal board, wherein the radial probe (6) and the PCB signal board are fixed after being fitted into the sensor housing (1).

9. A magnetic bearing assembly comprising a main shaft (11), characterized in that the magnetic bearing assembly further comprises an eddy current radial sensor according to any one of claims 1 to 8, which is sleeved on the main shaft (11).

10. Magnetic suspension bearing assembly according to claim 9, characterized in that the main shaft (11) comprises a middle shaft section (12) and annular protruding shafts (10) at both ends of the middle shaft section (12), the eddy current radial sensor is arranged on the middle shaft section (12), the detection end of the radial probe (6) faces the outer peripheral wall of the middle shaft section (12), and the central axis of the radial probe (6) intersects with and is perpendicular to the central axis of the middle shaft section (12).

11. Magnetic bearing assembly according to claim 9, wherein the number of eddy current radial sensors is two, the two eddy current radial sensors being arranged at intervals along the axial direction of the spindle (11).

12. A compressor comprising an eddy current radial sensor as claimed in any one of claims 1 to 8 or a magnetic bearing assembly as claimed in any one of claims 9 to 11.