CN116404817A

CN116404817A - Structure assembly of electric vortex sensor of integrated magnetic suspension motor

Info

Publication number: CN116404817A
Application number: CN202310302832.8A
Authority: CN
Inventors: 于新爱; 魏大忠; 田希晖; 郑领博; 郭清远
Original assignee: Beijing Gaofu Power Technology Co ltd
Current assignee: Beijing Gaofu Power Technology Co ltd
Priority date: 2023-03-23
Filing date: 2023-03-23
Publication date: 2023-07-07

Abstract

The invention discloses an integrated structure component of an electric vortex sensor of a magnetic suspension motor. The assembly consists of parts such as a metal bracket, a sensor probe assembly, a switching PCB (printed circuit board), a wire pressing plate, a temperature compensation plate, a cable, a fixing screw and the like. The sensor assembly is simplified in structure, the use of a switching metal support in the original sensor assembly is eliminated, and materials and processing cost are saved. The simplified design of the structure shortens the axial distance of the motor rotor to a certain extent. The sensor probe with the structure assembly arranged on different sides realizes one-time encapsulation and solidification, saves time cost and improves production efficiency.

Description

Structure assembly of electric vortex sensor of integrated magnetic suspension motor

Technical Field

The patent belongs to the technical field of magnetic suspension motors, and in particular relates to an integrated magnetic suspension motor sensor assembly structure which can be used as a detection device for radial and axial displacement of a motor high-speed rotor and can realize real-time monitoring and data feedback of motor rotor displacement and rotating speed.

Background

The eddy current displacement sensor has the advantages of good long-term working reliability, high sensitivity, strong anti-interference capability, high response speed, no influence of oil-water and other mediums, suitability for non-contact measurement and the like, and becomes a necessary choice for radial and axial displacement detection of the rotor of the magnetic suspension motor. The eddy current sensor is typically a wound metal coil with a certain number of turns. In order to prevent interference of external signals, the sensor coil is usually placed on a support with an insulating function, and is sealed by glue injection, and the encapsulated coil and the insulating support assembly are collectively called as a sensor probe assembly, which is called as a sensor probe for short.

The existing sensor structure is usually in two forms, one is to directly weld the outgoing line of the probe with the transmission cable, and throw out the lead through threads or some fixed structure. The structure is simpler, but the welding difficulty is extremely high due to the fact that the coil wire diameter and the wire diameter are too large. The other is to use each probe with a small PCB as a welded adapter plate, which solves the problem of difficult welding of the first structure, but increases the complexity of the structure. Because the coil diameter of the sensor is only 0.1 mm-0.3 mm, the sensor cannot be stretched for a long distance, and the sensor probe and the PCB board need to be installed in a short distance. At present, the sensor probe and the PCB are commonly fixed in a small metal support, and the small support is arranged on a large metal support in pairs according to the use condition after the sensor probe and the PCB are sequentially filled with glue and sealed. Each set of motors requires about 10 sets of sensor probe assemblies, i.e., contains 10 small mounts. When the motor is produced in a large quantity, the required quantity of the small support seats and the corresponding material and processing cost cannot be ignored. For the encapsulation of the small support, the sensor probe and the PCB are placed on different planes, the encapsulation needs to be performed by injecting glue respectively, the curing time of each step of encapsulation is more than or equal to 24 hours, the time consumption is long, and the efficiency is low. Therefore, it is necessary to develop a sensor assembly that can be encapsulated at a time and has a simple structure.

Depending on the requirements of use, no metal shield is available for a distance of at least 5mm to 6mm around the sensor probe, which results in a small holder head diameter size for the sensor probe to be at least 12mm larger than the probe diameter. In the magnetic levitation motor structural layout, the external dimension of the small support head where the sensor probe is located is a key factor affecting the axial dimension of the sensor assembly (i.e. the thickness of the sensor assembly), and this axial dimension is one of the factors affecting the length of the motor rotor. The longer the rotor, the poorer the rotor modal and kinetic performance with the same journal and structural form. In this way, in the design of the sensor structure, it is considered to minimize the axial dimension of the sensor assembly.

Disclosure of Invention

The technical solution of the invention is as follows: aiming at the problems existing in the prior art, the structural component is provided for directly mounting the sensor probe on a metal bracket and realizing disposable glue injection filling and sealing. The small support for fixing the sensor probe and the PCB is omitted, the axial size of the sensor assembly is reduced as much as possible through the layout of the sensor probe, and enough wiring positions are reserved on the existing structure.

The invention adopts the technical proposal that: an integrated structure component of an electric eddy current sensor of a magnetic suspension motor consists of a metal bracket, a sensor probe (an insulating support comprising a sensor coil and a fixed coil), a transfer PCB, a wire pressing plate, a temperature compensation plate and the like. The sensor probes for radial displacement detection are respectively arranged on the side walls of the middle of the metal bracket which are uniformly distributed along the circumference and are used in pairs relatively; two sensor probes for axial detection are distributed in cylindrical grooves machined on the surfaces of metal brackets in the included angle direction of two adjacent radial sensors at 180 degrees, the installation direction is perpendicular to the radial sensor probes, one of the two sensor probes is used for axial detection, and the other sensor probe is used for temperature compensation. The temperature compensation plate is directly arranged on the plane of the other side of the metal bracket, and the detection surface of the temperature compensation plate is kept at a certain distance from the sensor probe. All the PCB boards matched with the sensor probes are arranged in the grooves on the same side face of the metal bracket, and are close to the outlet positions of the probes as much as possible; and a line pressing plate is arranged at a position close to the tail end of the groove.

The middle of the integrated metal bracket is provided with 4 side walls perpendicular to the end face, the side walls are uniformly distributed along the circumference, and the side walls are symmetrical about the center. 4 round holes are respectively processed at positions perpendicular to the side wall and centered, and the diameter of each round hole and the mounting shaft neck of the sensor probe are in transition fit, so that stable mounting of the sensor probe before encapsulation is ensured. Cylindrical grooves with certain depth are respectively processed at 2 positions in the direction of 45 degrees between the two side walls, the size of each groove is used for ensuring that a certain distance around the sensor probe is not interfered by metal objects, and the depth accords with radial detection requirements. The center position of the cylindrical groove is provided with round holes for installing radial sensor probes, the size of the round holes is the same as that of 4 radial cylindrical holes, 3 small holes with the diameter of about 3mm are uniformly distributed around the round holes along a 180-degree circular arc, and during filling and sealing, glue flows to the back of the assembly through the small holes, so that one-time filling and sealing is realized. The sensor assemblies are generally arranged at two ends of A, B of the magnetic suspension motor respectively, as shown in fig. 1, for the sensor assemblies for the end B of the motor, a step structure shown in fig. 3 can be processed at the position C of the bracket, and the step structure is used for mounting a speed sensor, a round hole connected with a speed sensor mounting groove is used for allowing a sensor pin to pass through, and meanwhile, glue is injected during filling and sealing. The edge of the bracket is processed into a relatively large-area plane area along the circumferential direction for coiling and fixing the cable, and 8 through holes uniformly distributed on the circumferential edge are the mounting holes of the sensor assembly and the magnetic suspension motor system.

The sensor probe is placed according to the hole site on the metal support, and the PCB board that is used of joining in marriage then is placed in corresponding rectangle recess respectively, welds and with the fixed whole injecting glue embedment of back of cable. The line ball board is placed in the recess the same as the circuit board or recess edge, and its effect is closely fixed cable one, prevents that the solder joint from breaking because of cable stretching, has played the effect of isolating embedment space simultaneously. After welding, the wire pressing plate, the output wire cable and the groove for placing the circuit board form a relatively closed space, and overflow of glue during filling and sealing can be avoided. The structure eliminates the use of the original small support, and the structure of the metal support is simpler than that of the original support, so that the processing cost is lower.

After the sensor probe is installed, the reserved probe outgoing line is welded with a corresponding node of the PCB, and is welded with the outgoing cable through the PCB, and the outgoing cable is fixed by the wire pressing plate at a short distance of the PCB. The cables penetrating out of the line pressing plate are coiled on a plane, close to the outer side, of the metal support, are respectively combined and fixed, and are output from a reserved line outlet hole site of the motor. After the probe is installed, the cable is welded and the line pressing plate is fastened, the whole encapsulation treatment can be performed. Under the cooperation of prefabricated embedment frock, insulating glue directly spreads and annotates in the recess at PCB board place, embedment axial sensor probe's glue then pours into the opposite side through the injecting glue hole that the metal support reserved to realize once embedment and solidification shaping. Compared with the existing process of twice filling and sealing and respectively curing, half of time is saved, and the production efficiency is remarkably improved.

Compared with the existing structure, the invention has the advantages that: the design adopts the structure that the radial and axial sensor probes are directly installed on the metal bracket, the use of the small support used for switching installation is eliminated, and the material and the processing cost are saved. The design of the axial dimension (thickness) of the metal bracket depends on the diameter of the sensor probe, but not the diameter of the small support head with larger dimension, so that the axial dimension (thickness) of the sensor assembly is effectively shortened, and the aim of shortening the axial dimension of the motor rotor is fulfilled. Through the improved design and the component layout of the support structure, the disposable glue injection filling, sealing and curing are realized, the time cost is effectively reduced, and the effective efficiency is improved.

Drawings

FIG. 1 is a front and bottom view of the sensor assembly of the present patent;

FIG. 2 is a front view, a bottom view and a partial sectional view of the metal bracket of the present patent;

FIG. 3 is a cross-sectional view of the speed sensor mounting structure of the present patent;

FIG. 4 is a diagram of the components of the medium voltage line plate and the temperature compensation plate of the present patent;

reference numerals illustrate:

1-a metal bracket; 2-a sensor probe; 3-a PCB board; 4-line pressing plates; 5-a temperature compensation plate; 6-mounting a screw 1; 7-a cable; 8-mounting screws 2; c-a speed sensor mounting clamping groove;

Detailed Description

The present structure is described in detail below with reference to the accompanying drawings and detailed description.

As shown in fig. 1, the patent is an integrated magnetic levitation motor eddy current sensor assembly structure, which consists of a metal bracket 1, a sensor probe 2, a PCB board 3, a wire pressing plate 4, a temperature compensation plate 5, a cable 7,

mounting screws

6 and 8 and the like. The 4 radial sensor probes are respectively arranged in the holes 101 shown in fig. 2, the directions of the probes are perpendicular to the side wall 102, and the probes are uniformly distributed along the circumference. The 2 axial sensor probes are respectively arranged at the central holes 105 in the cylindrical grooves shown in fig. 2, and the directions of the two axial sensor probes are perpendicular to the inner bottom surfaces 107 of the grooves. The PCB 3 is installed in the recess 104 department that figure 2 shows respectively, and the wire outgoing welding of sensor probe is on PCB 3, and again via PCB 3 and cable 7 welding, cable 7 is worn out through the side opening of line ball board 4, winds into bundles at integral type metal support outer lane according to trend, fixed back again by motor housing. The wire pressing plate 4 is respectively fixed at the groove 104 or the edge of the groove corresponding to the PCB 3 by the mounting screw 8, and plays a role in dividing and sealing the potting area while pressing the cable. After the sensor probe 2, the PCB 3, the wire pressing plate 4 and the cable 7 are assembled and welded, the whole encapsulation treatment is carried out with the metal bracket 1 under the action of an encapsulation tool. During encapsulation, the plane where the PCB is located is upwards placed, and the encapsulation tool is arranged below the metal bracket 1. The insulating glue can be directly injected into the PCB groove on the assembly, and meanwhile, the insulating glue is injected into the bottom surface of the sensor assembly through the opening 106 shown in fig. 2, and is fixed in a preset area by the encapsulating tool and the bracket structure, so that the encapsulating of the axial sensor probe is realized. If a speed sensor is installed, an insulating glue may be injected into the bottom of the assembly through the hole at 108 shown in FIG. 2 to complete the potting of the speed sensor. The whole encapsulation process is completed once, and after curing treatment, the assembly form and the motor are integrally installed and used.

The metal bracket 1 is provided with a radial hole site 101 (4) and a corresponding positioning surface 102 (4), an axial hole site 105 (2) and a corresponding positioning surface 107 (2), and can be directly used for mounting the radial and axial sensor probes 2; the grooves 104 (6) are arranged on the same side face of the sensor bracket 1, so that the potting operation after the cable welding is convenient; considering that the axial sensor probe is positioned on the opposite end face of the PCB, 6 glue injection holes 106 and 1 glue injection hole 108 for filling and sealing the speed sensor are added to the structure, so that one-time filling and sealing is facilitated. The bracket 1 is provided with an annular surface for coiling and fixing the cable near the outer ring part so as to facilitate distributing the cable according to the need.

The structure of the line pressing plate 4 and the structure of the temperature compensation plate 5 are shown in fig. 3. The wire pressing plate 4 forms a closed area together with the groove 104 and the cable shown in fig. 2, so that direct glue filling is facilitated. The temperature compensation plate 5 is set by functional requirements, which are not described here.

The foregoing is merely one application of the present invention, and is not intended to limit the invention. It should be noted that the names and forms of the components described in the present invention may be different, and all modifications, additions and improvements made according to the construction, features and principles of the present invention are considered as the protection scope of the present invention.

Claims

1. An integrated structure component of an electric eddy current sensor of a magnetic suspension motor consists of a metal bracket, a sensor probe component (an insulating support comprising a sensor coil and a fixed coil), a transfer PCB, a line pressing plate, a temperature compensation plate and the like. The sensor probe is characterized in that components such as a radial sensor probe, an axial sensor probe, a PCB (printed Circuit Board) for probe matching, a line pressing plate, a temperature compensation plate and the like are integrated on a metal bracket, so that a rotary mounting support for mounting the sensor probe and the PCB is omitted, and materials and processing cost are saved. All the PCB boards are placed in grooves on the same side of the support, the wire pressing boards are placed at the tail ends of the grooves which are the same as the PCB boards, and the wire pressing boards play a role in isolating a potting region while pressing the wire. Two axial sensor probes are placed on one side surface of the metal support opposite to the PCB, and round glue injection holes are reserved around the probes, so that one-time encapsulation is conveniently completed.

2. An integrated magnetic levitation motor electrical eddy current sensor structural assembly according to claim 1, wherein: all parts related to the sensor assembly are integrated on one metal bracket, so that the original rotary mounting small support for mounting the sensor probe and the matched PCB is omitted, the number of the two ends of each motor A, B of the small support is about 10, the structure is relatively complex, and the processing cost is high. Therefore, the scheme simplifies the structure and simultaneously saves a great amount of materials and processing cost.

3. An integrated magnetic levitation motor electrical eddy current sensor structural assembly according to claim 1, wherein: the PCB board that uses in the sensor module all installs in metal support's homonymy to utilize the arrangement of line ball board to effectively keep apart the embedment region, open embedment space is more convenient for injecting glue operation. In consideration of the fact that the sensor probe placed on the other side of the metal support needs to be encapsulated, glue injection holes are formed in the support structure around the sensor probe mounting holes, so that one-time encapsulation and solidification are convenient, the problem that the primary rotation mounting small support structure needs to be encapsulated twice and solidified respectively (each time is more than or equal to 24 hours) and is too long in time is solved, and production efficiency is obviously improved.

4. An integrated magnetic levitation motor electrical eddy current sensor structural assembly according to claim 1, wherein: in the assembly, the radial sensor probe is directly arranged on the side wall of the metal bracket, which is circumferentially and uniformly distributed at the center of the metal bracket, the diameter of the probe is about 5-7 mm, and the radial mounting hole of the probe is positioned at the middle part of the thickness direction of the metal bracket, so that the thickness (i.e. the axial dimension) of the metal bracket can be reasonably designed according to the diameter of the sensor probe, and the dimension can be reduced as far as possible. In the magnetic levitation motor structure, the sensor assemblies are distributed at both ends of the motor shaft A, B, and the axial dimension thereof is one of factors affecting the length of the rotor, which is an important factor affecting the mode and rotor dynamics parameters thereof, thereby further affecting the motor performance. Therefore, the simplified design of the structure is beneficial to improving the rotor dynamic parameters, so that the stability and the reliability of the magnetic levitation motor are further improved.