1. A magnetic suspension motor shaft radial displacement detection device is characterized by comprising a sensor bracket (1) and a plurality of radial sensors (2); the sensor bracket (1) is provided with a shaft hole (3) for a motor shaft to pass through, and the sensing end of the radial sensor (2) is aligned with the motor shaft in the radial direction; the plurality of radial sensors (2) are respectively and independently fixed on the sensor support (1), and the plurality of radial sensors (2) are not connected with each other.

2. A device for detecting the radial displacement of a shaft of a magnetic levitation motor as claimed in claim 1, characterized in that four radial sensors (2) are arranged opposite to each other two by two in the radial direction of the sensor holder (1) and the axes of the two pairs of radial sensors (2) are perpendicular to each other.

3. A device for detecting the radial displacement of a shaft of a magnetic levitation motor as recited in claim 1, characterized in that the radially innermost sides of the radial sensors (2) are in the shape of circular arcs, and the radially innermost circular arcs of the plurality of radial sensors (2) are attached to the same circle.

4. A device for detecting the radial displacement of a shaft of a magnetic levitation motor as claimed in claim 1, characterized in that the radial sensor (2) is of horseshoe-shaped construction.

5. A magnetic suspension motor shaft radial sensor positioning device is characterized by comprising a sensor bracket (1), a plurality of radial sensors (2) and a positioning tool (4); the sensor holder (1) and the plurality of radial sensors (2) are as claimed in claim 1; the sensor bracket (1) is detachably connected with the positioning tool (4); the positioning tool (4) is provided with a cylindrical positioning boss (5) and a positioning groove (6) in a ring shape, the positioning boss (5) penetrates through the shaft hole (3), and the cylindrical outer surface of the positioning boss (5) is attached to the radially innermost arc of the radial sensor (2); the bottom surface of the sensor support (1) is attached to the bottom surface of the positioning groove (6), and the arc surface of the radially outermost side of the sensor support (1) is attached to the arc side surface of the positioning groove (6).

6. The positioning device for the radial sensor of the magnetic suspension motor shaft as claimed in claim 5, characterized in that the sensor holder (1) and the positioning tool (4) are connected by screws or bolts.

7. A method for positioning a radial sensor of a magnetic levitation motor shaft, the method using the positioning device of claim 5, the method comprising the steps of:

(S1) attaching the bottom surface of the sensor support (1) to the bottom surface of the positioning groove (6), and attaching the arc surface of the radially outermost side of the sensor support (1) to the arc side surface of the positioning groove (6);

(S2) fastening the sensor bracket (1) and the positioning tool (4) by using screws;

(S3) the arcs of the radial innermost sides of the four groups of radial sensors (2) are attached to the outer surface of the cylinder of the positioning boss (5) to position the positioning boss and the positioning boss is installed on the sensor bracket (1);

(S4) after the screws of the sensor support (1) and the positioning tool (4) are removed, the sensor support (1) is installed on the blower shell, and the sensing end of the radial sensor (2) is connected with the motor shaft to complete the positioning process of the radial sensor of the magnetic suspension motor shaft.

8. A magnetic levitation blower, characterized in that the blower comprises a motor shaft (11), a radial bearing assembly (12), an axial bearing assembly (13), a sensor holder (1) and a plurality of radial sensors (2); the sensor holder (1) and the plurality of radial sensors (2) are as claimed in claim 1; the supporting ends of the radial bearing assemblies (12) are respectively contacted with the two ends of the motor shaft (11), and the limiting end of the axial bearing assembly (13) is connected with one end of the motor shaft (11).

9. The magnetic levitation blower according to claim 8, characterized in that the axial bearing assembly (13) comprises a thrust disc (7), an axial bearing stator assembly (8) and a bearing outer ring (9); the axial bearing stator combination (8) comprises a first bearing stator (81) and a second bearing stator (82); the first bearing stator (81) is provided with heat dissipation holes (83) penetrating along the left-right direction, the second bearing stator (82) is provided with heat dissipation grooves (84) distributed along the up-down direction and concave inwards, and the upper ends of the heat dissipation grooves (84) are communicated with the outside through the heat dissipation holes (83); a first heat dissipation gap (71) is formed between two side faces of the lower end of the thrust disc (7) and the corresponding inner side face of the bearing outer ring (9), and a second heat dissipation gap (72) is formed between two side faces of the upper end of the thrust disc (7) and the corresponding inner side face of the second bearing stator (82); the bearing outer ring (9) is provided with a first cavity (91) and a second cavity (92) communicated with the outside, the upper end of the first heat dissipation gap (71), the lower end of the heat dissipation groove (84) and the lower end of the second heat dissipation gap (72) are respectively communicated with the first cavity (91), and the upper end of the second heat dissipation gap (72) is communicated with the second cavity (92); the second cavity (92) comprises a vertical cavity (93) and a horizontal cavity (94), the lower end of the vertical cavity (93) is communicated with the upper end of the second heat dissipation gap (72), and the upper end of the vertical cavity (93) is communicated with the outside through the horizontal cavity (94).

10. A magnetic levitation blower according to claim 9, characterised in that the vertical cavity (93) is located below the centre of symmetry of the horizontal cavity (94).

Background

The magnetic suspension motor shaft has high rotating speed, and in order to avoid the motor shaft from generating large radial jitter, the radial displacement change of the motor shaft in the rotating process needs to be detected in real time, and the radial jitter is immediately inhibited, so that the motor shaft is ensured to rotate at high speed in an ultra-stable and ultra-static state. The radial detection of the motor shaft is generally non-contact, namely, a distance sensor is used for detecting in real time, the variation of the detection result exceeds a preset value and is judged to generate radial jitter, and active inhibition needs to be performed in time.

The Chinese utility model patent application (publication No. CN209945245U, published: 20200114) discloses a magnetic suspension motor shaft radial displacement detection device, which comprises an inductance coil, an annular mounting plate and a circuit board, wherein the circuit board is mounted on the top surface of the mounting plate; a first through hole is formed in the middle of the mounting plate, a coil fixing groove is formed in the edge of the first through hole, clamping plates are arranged on the edges of the coil fixing groove, and the inductance coil is fixed between the two clamping plates through glue; the clamping plate increases the adhesive area, and the induction coil is firmly positioned; the mounting of the small-volume induction coil is realized in an adhesive fixing mode, the yield is improved, and the manufacturing cost of the eddy current sensor is reduced; the volume of the inductance coil is small, so that the whole magnetic suspension motor shaft radial displacement detection device is compact in structure, small in volume, free of redundant design, suitable for mass production and beneficial to miniaturization of equipment using the eddy current sensor; the inductance coils are small in size and can be arranged in a plurality of positions at the same time, so that accurate dynamic displacement signals of the motor shaft can be obtained.

The prior art has the following defects: the radial sensor is annular, has a complex structure and a large volume, and has a large part of redundant connecting material, so that the material of the sensor is wasted.

Disclosure of Invention

The purpose of the invention is: aiming at the problems, the magnetic suspension motor shaft radial displacement detection device reduces the consumption of sensor materials and reduces the cost of the radial sensor by removing redundant connecting materials of the radial sensor.

In order to achieve the purpose, the invention adopts the following technical scheme:

a magnetic suspension motor shaft radial displacement detection device is characterized by comprising a sensor bracket and a plurality of radial sensors; the sensor bracket is provided with a shaft hole for the motor shaft to pass through, and the sensing end of the radial sensor is radially aligned with the motor shaft; the plurality of radial sensors are respectively and independently fixed on the sensor bracket, and the plurality of radial sensors are not connected with each other.

Preferably, the four radial sensors are distributed oppositely two by two along the radial direction of the sensor support, and the axes of the two pairs of radial sensors are perpendicular to each other.

Preferably, the radially innermost side of the radial sensor is formed in a circular arc shape, and the circular arcs of the radially innermost sides of the plurality of radial sensors are fitted to the same circular shape.

Preferably, the radial sensor is of horseshoe-type construction.

In addition, the invention also discloses a positioning device for the radial sensor of the magnetic suspension motor shaft, which comprises a sensor bracket, a plurality of radial sensors and a positioning tool; the sensor bracket is detachably connected with the positioning tool; the positioning tool is provided with a cylindrical positioning boss and a positioning groove in a ring shape, the positioning boss penetrates through the shaft hole, and the outer surface of the positioning boss cylinder is attached to the radially innermost arc of the radial sensor; the bottom surface of the sensor support is attached to the bottom surface of the positioning groove, and the arc surface of the radially outermost side of the sensor support is attached to the arc side surface of the positioning groove.

Preferably, the sensor bracket and the positioning tool are connected through screws or bolts.

In addition, the invention also discloses a positioning method of the magnetic suspension motor shaft radial sensor, which adopts a positioning device of the magnetic suspension motor shaft radial sensor, and the method comprises the following steps:

(S1) attaching the bottom surface of the sensor support to the bottom surface of the positioning groove, and attaching the arc surface of the radially outermost side of the sensor support to the arc side surface of the positioning groove;

(S2) fastening the sensor bracket and the positioning tool by using a screw;

(S3) the arcs at the radial innermost sides of the four groups of radial sensors are attached to the outer surface of the positioning boss cylinder to position the positioning boss cylinder and are installed on the sensor bracket;

(S4) after the screws of the sensor support and the positioning tool are removed, the sensor support is installed on the blower shell, and the induction end of the radial sensor is connected with the motor shaft to complete the positioning process of the radial sensor of the shaft of the magnetic suspension motor.

In addition, the invention also discloses a magnetic suspension blower which comprises a motor shaft, a radial bearing assembly, an axial bearing assembly, a sensor bracket and a plurality of radial sensors; the supporting ends of the radial bearing assemblies are respectively contacted with two ends of the motor shaft, and the limiting end of the axial bearing assembly is connected with one end of the motor shaft.

Preferably, the axial bearing assembly comprises a thrust disc, an axial bearing stator combination and a bearing outer ring; the axial bearing stator combination comprises a first bearing stator and a second bearing stator; the first bearing stator is provided with heat dissipation holes penetrating along the left-right direction, the second bearing stator is provided with heat dissipation grooves distributed along the up-down direction and concave inwards, and the upper ends of the heat dissipation grooves are communicated with the outside through the heat dissipation holes; a first heat dissipation gap is formed between two side faces of the lower end of the thrust disc and the corresponding inner side face of the bearing outer ring, and a second heat dissipation gap is formed between two side faces of the upper end of the thrust disc and the corresponding inner side face of the second bearing stator; the bearing outer ring is provided with a first cavity and a second cavity communicated with the outside, the upper end of a first heat dissipation gap, the lower end of a heat dissipation groove and the lower end of a second heat dissipation gap are respectively communicated with the first cavity, and the upper end of the second heat dissipation gap is communicated with the second cavity. The second cavity comprises a vertical cavity and a horizontal cavity, the lower end of the vertical cavity is communicated with the upper end of the second heat dissipation gap, and the upper end of the vertical cavity is communicated with the outside through the horizontal cavity.

Preferably, the vertical cavity is located below the center of symmetry of the horizontal cavity.

The magnetic suspension motor shaft radial displacement detection device adopting the technical scheme has the advantages that:

divide into a plurality of independent radial sensors and fix respectively to the sensor support with interconnect's radial sensor on, get rid of radial sensor's unnecessary connecting material, make the sensor consumptive material reduce two-thirds, practiced thrift the cost greatly.

Drawings

Fig. 1 is a schematic structural view of a magnetic levitation blower of the present invention.

Fig. 2 and 3 are schematic structural diagrams of a positioning device of a magnetic levitation motor shaft radial sensor.

Fig. 4 and 5 are schematic structural diagrams of the positioning tool.

Fig. 6 is a schematic structural diagram of a conventional radial sensor.

Fig. 7 is a schematic structural diagram of a radial sensor of the present invention.

FIG. 8 is a schematic view of an axial bearing assembly.

73-screws, L1-heat dissipation air duct.

Detailed Description

The following describes in detail embodiments of the present invention with reference to the drawings.

Example 1

A magnetic suspension motor shaft radial displacement detection device comprises a sensor bracket 1 and a plurality of radial sensors 2; the sensor bracket 1 is provided with a shaft hole 3 for a motor shaft to pass through, and the sensing end of the radial sensor 2 is aligned with the motor shaft in the radial direction; the plurality of radial sensors 2 are individually fixed to the sensor holder 1, and the plurality of radial sensors 2 are not connected to each other. The four radial sensors 2 are distributed opposite to each other two by two along the radial direction of the sensor support 1, and the axes of the two pairs of radial sensors 2 are perpendicular to each other. In this kind of mode, divide into a plurality of independent radial sensors and fix respectively to sensor support 1 with the radial sensor of interconnect on, get rid of radial sensor's unnecessary connecting material, make the sensor consumptive material reduce two-thirds, practiced thrift the cost greatly.

The radially innermost side of the radial sensor 2 is in the shape of an arc, and the radially innermost arcs of the plurality of radial sensors 2 are attached to the same circle. The radial sensor 2 is of horseshoe-type construction.

In addition, the invention also discloses a positioning device for the radial sensor of the magnetic suspension motor shaft, which comprises a sensor bracket 1, a plurality of radial sensors 2 and a positioning tool 4; the sensor bracket 1 is detachably connected with the positioning tool 4; the positioning tool 4 is provided with a cylindrical positioning boss 5 and a positioning groove 6 in a ring shape, the positioning boss 5 penetrates through the shaft hole 3, and the cylindrical outer surface of the positioning boss 5 is attached to the radially innermost circular arc of the radial sensor 2; the bottom surface of the sensor support 1 is attached to the bottom surface of the positioning groove 6, and the radial outermost side arc surface of the sensor support 1 is attached to the arc side surface of the positioning groove 6. The sensor bracket 1 is connected with the positioning tool 4 through screws or bolts.

In addition, the invention also discloses a positioning method of the magnetic suspension motor shaft radial sensor, which adopts a positioning device of the magnetic suspension motor shaft radial sensor, and the method comprises the following steps:

(S1) attaching the bottom surface of the sensor support 1 to the bottom surface of the positioning groove 6, and attaching the arc surface of the outermost side of the sensor support 1 to the arc side surface of the positioning groove 6;

(S2) fastening the sensor bracket 1 and the positioning tool 4 by using screws;

(S3) the arcs of the radial innermost sides of the four groups of radial sensors 2 are attached to the outer surface of the cylinder of the positioning boss 5 to position the positioning boss and the positioning boss is installed on the sensor bracket 1;

(S4) after the screws of the sensor support 1 and the positioning tool 4 are removed, the sensor support 1 is installed on the shell of the air blower, and the sensing end of the radial sensor 2 is connected with the motor shaft to complete the positioning process of the radial sensor of the magnetic suspension motor shaft.

In the mode, the radial position of the sensor support 1 is positioned by the arc side surface of the positioning groove 6, the radial position of the radial sensor 2 is positioned by the outer surface of the positioning boss 5 cylinder, and the axial position of the radial sensor 2 is positioned by the top surface of the sensor support 1; therefore, the radial sensor 2 and the sensor support 1 have determined relative positions in the radial direction and the axial direction, and the installation accuracy of the radial sensor 2 is guaranteed.

In addition, the invention also discloses a magnetic suspension blower which comprises a motor shaft 11, a radial bearing assembly 12, an axial bearing assembly 13, a sensor bracket 1 and a plurality of radial sensors 2; the supporting ends of the plurality of radial bearing assemblies 12 are respectively contacted with the two ends of the motor shaft 11, and the limiting end of the axial bearing assembly 13 is connected with one end of the motor shaft 11.

The axial bearing assembly 13 comprises a thrust disc 7, an axial bearing stator assembly 8 and a bearing outer ring 9; the axial bearing stator assembly 8 includes a first bearing stator 81 and a second bearing stator 82; the first bearing stator 81 is provided with heat radiation holes 83 penetrating along the left-right direction, the second bearing stator 82 is provided with heat radiation grooves 84 distributed along the up-down direction and concave inwards, and the upper ends of the heat radiation grooves 84 are communicated with the outside through the heat radiation holes 83; a first heat dissipation gap 71 is formed between two side faces of the lower end of the thrust disc 7 and the corresponding inner side face of the bearing outer ring 9, and a second heat dissipation gap 72 is formed between two side faces of the upper end of the thrust disc 7 and the corresponding inner side face of the second bearing stator 82; the bearing outer ring 9 is provided with a first cavity 91 and a second cavity 92 communicated with the outside, the upper end of the first heat dissipation gap 71, the lower end of the heat dissipation groove 84 and the lower end of the second heat dissipation gap 72 are respectively communicated with the first cavity 91, and the upper end of the second heat dissipation gap 72 is communicated with the second cavity 92; the second cavity 92 includes a vertical cavity 93 and a horizontal cavity 94, a lower end of the vertical cavity 93 is communicated with an upper end of the second heat dissipation gap 72, and an upper end of the vertical cavity 93 is communicated with the outside through the horizontal cavity 94. The vertical cavity 93 is located below the center of symmetry of the horizontal cavity 94. When the thrust disc 7 rotates at a high speed, the airflow is driven to flow, external airflow enters the first cavity 91 along the first heat dissipation gap 71 and enters the first cavity 91 along the heat dissipation holes 83 and the heat dissipation grooves 84 in sequence, and then the airflow in the first cavity 91 enters the second cavity 92 along the second heat dissipation gap 72 and flows to the outside of the bearing, so that the airflow flowing process is completed; the heat dissipation air path is formed in the air flow flowing process, the temperature of a thrust bearing stator and a winding is obviously reduced, and the thrust bearing assembly can work safely and stably under a better working condition.