A horizontal mounting method for a high-power semi-direct drive permanent magnet motor

Abstract

This invention belongs to the field of synchronous motor assembly, specifically a horizontal mounting method for a high-power semi-direct drive permanent magnet motor. It solves the technical problem of assembly failure caused by large shaft deformation during the horizontal mounting of a high-power semi-direct drive permanent magnet motor, resulting in the stator and rotor adhering together. This invention installs a guide positioning shaft and a guide positioning sleeve at the front end of the rotor assembly shaft; and a guide positioning screw is installed between the rear end cover and the stator assembly. When the rear end cover and rotor assembly move axially, the guide positioning screw moves along with the rear end cover and enters the through holes around the rear end of the stator assembly, ensuring that the rotor assembly does not experience axial movement during assembly. With the smooth movement of the guide positioning sleeve assembly and the guide positioning screw, the rotor assembly slowly enters the stator assembly axially until the stator and rotor assemblies are axially aligned, and the bearing at the front end of the rotor assembly enters the bearing housing. At this point, the guide sleeve assembly is disassembled, and the rotor bearing front end cover is installed, completing the installation.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of synchronous motor assembly, and particularly relates to a horizontal assembly method for a high-power semi-direct-drive permanent magnet motor. BACKGROUND

[0002] The assembly of a high-power permanent magnet motor has always been a process difficulty. The rotor with magnetic steel has a very strong adsorption force, and the air gap between the stator and the rotor is small. During the general assembly, a great radial one-side magnetic pulling force is generated due to the eccentricity of the stator and the rotor, and collision occurs, which seriously causes the stator and the rotor to be adsorbed together and difficult to be separated, and even causes the stator and the rotor to be scrapped. Especially for a high-power semi-direct-drive permanent magnet synchronous motor, the iron core is longer, the inner circle of the stator iron core is larger, and the one-side magnetic pulling force caused by the eccentricity of the rotor during assembly is larger. During assembly, the deformation of the rotating shaft is large, and the stator and the rotor are easily adsorbed together to cause assembly failure.

[0003] Specifically, the existing horizontal assembly technical scheme is to use a non-standard permanent magnet general assembly machine modified like a boring machine. The assembly scheme is as follows:

[0004] (1) The stator of the permanent magnet synchronous motor is assembled and fixed on the sliding table of the general assembly machine, and a dummy rotor is used to correct the coaxiality of the stator and the rotor.

[0005] (2) The rotor assembly and the auxiliary extension shaft are installed between the main shaft center and the tailstock center, and the stator assembly is moved to align the stator assembly and the rotor shaft assembly.

[0006] The existing horizontal assembly technical scheme has the following disadvantages:

[0007] (1) The rotor is installed between the main shaft center and the tailstock center, and the entire rotor assembly and the extension shaft can pass through the stator assembly by means of the auxiliary extension shaft. The total length of the rotor assembly and the extension shaft is more than twice the total length of the entire motor, so that the span supported between the two centers is large, and the deformation of the rotating shaft is large during assembly, which easily causes the stator and the rotor to be adsorbed together and causes assembly failure.

[0008] (2) During assembly, the stator of the permanent magnet synchronous motor is assembled and fixed on the sliding table of the general assembly machine, and the coaxiality of the stator and the rotor is adjusted by repeatedly measuring the stator support with a dummy rotor and a plug gauge. The coaxiality of the stator assembly and the rotor assembly is limited by the level of the operator and the machining precision of the dummy rotor. SUMMARY

[0009] The application provides a horizontal assembly method for a high-power semi-direct-drive permanent magnet motor to solve the technical problem that the large deformation of the rotating shaft during the horizontal assembly of the high-power semi-direct-drive permanent magnet motor causes the stator and the rotor to be adsorbed together and causes assembly failure.

[0010] The application is implemented by adopting the following technical scheme: a horizontal assembly method of a high-power semi-direct-drive permanent magnet motor, comprising the following steps: (1) installing a guide positioning shaft and a guide positioning sleeve assembly at the front end of a rotating shaft of a rotor assembly; the guide positioning sleeve assembly is sleeved on the outer periphery of the guide positioning shaft to install the guide positioning shaft at the front end of the rotating shaft, and the guide positioning sleeve assembly extends into a bearing chamber of a front end cover and is in clearance fit with the bearing chamber;

[0011] (2) after the rotor assembly and the rear end cover are assembled, the end of the rotating shaft extends out of the bearing chamber of the rear end cover, and the extended part is lifted by an L-shaped balance lifting appliance to make the rotating shaft in a horizontal suspension state; the rear end cover and the stator assembly are connected by a plurality of guide positioning rods, the guide positioning rods are in clearance fit with a plurality of through holes arranged on the periphery of the rear end cover and are fixedly connected between the rear end cover, so as to ensure the coaxiality of the rear end of the rotor assembly and the stator assembly;

[0012] (3) when the rear end cover and the rotor assembly move in the axial direction, the guide positioning rods move with the rear end cover and enter the through holes on the periphery of the rear end of the stator assembly, so that the rotor assembly does not move axially during assembly, and the rotor assembly slowly enters the stator assembly in the axial direction with the stable movement of the guide positioning sleeve assembly and the guide positioning rods, until the stator assembly and the rotor assembly are axially aligned, the bearing at the front end of the rotor assembly enters the bearing chamber, at this time, the guide sleeve assembly is disassembled, the front end cover of the rotor bearing is installed, and the installation of the rotor assembly is completed.

[0013] The design and application of the guide positioning rods and the guide sleeve assembly effectively improve the accuracy of axial positioning, and the L-shaped balance lifting appliance bears the gravity of the rotor assembly, facilitating the movement and axial adjustment of the rotor assembly.

[0014] The horizontal assembly method of the high-power semi-direct-drive permanent magnet motor can effectively solve the problem that the large deformation of the rotating shaft causes the stator and the rotor to be adsorbed together during the horizontal assembly process of the high-power semi-direct-drive permanent magnet synchronous motor, and can save the design and manufacture of a non-standard permanent magnet assembly machine similar to a boring machine, thereby reducing the process manufacturing cost. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 A horizontal assembly method of a high-power semi-direct-drive permanent magnet motor.

[0016] 1-L-shaped balance lifting appliance; 2-rear end cover; 3-guide positioning screw; 4-stator assembly; 5-front end cover; 6-magnetic force balance lead screw; 7-rotor assembly; 8-guide positioning shaft; 9-first guide positioning sleeve; 10-second guide positioning sleeve; 11-third guide positioning sleeve. DETAILED DESCRIPTION

[0017] The structures of various auxiliary toolings designed in the application are as follows:

[0018] In step (1), the guide sleeve assembly consists of a first guide positioning sleeve, a second guide positioning sleeve, and a third guide positioning sleeve. The end of the guide positioning shaft extends radially outward to form a flared section, which rests on the front end of the rotating shaft. The inner wall of the front end of the third guide positioning sleeve has a constricted structure, which fits around the outside and front side of the flared section of the guide positioning shaft. The remaining part of the third guide positioning sleeve fits around the circumference of the front end of the rotating shaft and is in close contact with the front end face of the rotating shaft bearing. The second guide positioning sleeve and the first guide positioning sleeve are sequentially fitted onto the guide positioning shaft next to the third guide positioning sleeve. The fitting diameter between the guide positioning sleeve and the front end cover bearing chamber is φ460mm, and the fitting clearance is 0.2mm.

[0019] The guide positioning rod includes multiple guide positioning screws and multiple magnetic pull balancing screws. The end sections of the guide positioning screws and magnetic pull balancing screws are respectively installed in the through holes of the rear end cover, and the front ends are inserted into the through holes around the rear end of the stator assembly.

[0020] The L-shaped balancing hoist is used after rotating 90 degrees. A slider is movably fitted on its horizontal section and connected to the lifting mechanism. A fixed sleeve is installed at the bottom of the vertical section for hoisting the end section of the rotating shaft. The slider is positioned with the L-shaped balancing hoist by positioning screws.

[0021] The technical solution of the present invention is as follows:

[0022] (1) Both ends of the rotor are movable and can move axially. The coaxiality of the front end of the rotor assembly in item 7 is guaranteed by the cooperation between the guide positioning shaft in item 8, guide positioning sleeve one in item 9, guide positioning sleeve two in item 10, guide positioning sleeve three in item 11, which are installed coaxially with the rotor and the bearing chamber of the front end cover in item 5.

[0023] (2) The coaxiality of the rear end of the rotor assembly in item 7 is ensured by the cooperation of the 12 guide positioning screws in item 3 and the 12 through holes on the rear end cover in item 2;

[0024] (3) The weight of the rotor assembly in item 7 is borne by the L-shaped balance hanger in item 1, which is connected to the rear end of the rotor assembly;

[0025] (4) The axial magnetic pull force of the stator assembly in item 4 and the rotor assembly in item 7 is balanced by the four magnetic pull balancing screws in item 6 connected to the rear end cover in item 2.

[0026] The magnetic pull balancing screw is an enlarged, fully threaded screw. During assembly, the rotor is connected to the screw, which is used to balance the axial magnetic pull. Under normal circumstances, the stator and rotor cores of the motor are aligned, and the magnetic pull acts radially, without generating an axial magnetic pull. When the stator and rotor are not fully aligned, the air gap between them is effectively lengthened. Since the magnetic lines of force preferentially choose the path with lower magnetic reluctance, and the shorter the distance through the air gap, the lower the magnetic reluctance, the axial magnetic force component, i.e., the axial magnetic pull, is generated when the magnetic lines of force attempt to pass through the air gap in the shortest possible distance. During assembly, a screw must be used to balance the axial magnetic pull of the permanent magnet motor; otherwise, rotor misalignment may occur during assembly, causing axial collision between the stator and rotor.

[0027] (5) In this scheme, as the rotor assembly of item 7 is axially advanced, although the single-sided magnetic pull of the motor continues to increase, the axial support span of the rotor continues to decrease. This overcomes the problem of the large deformation of the shaft in the horizontal mounting scheme causing the stator and rotor to stick together.

[0028] (6) In this solution, since the rotor assembly axis of item 7 is not fixed, the axial magnetic pull of the permanent magnet motor must be considered during assembly. Otherwise, the rotor may move axially during assembly, which may cause axial collision between the stator and rotor, or even personal injury to the assembly personnel. This solution uses four item 6 magnetic pull balancing screws connected to the rear end cover of item 2 to balance the axial magnetic pull, which solves this problem well.

[0029] The following is in conjunction with the appendix Figure 1 The present invention will be further described below.

[0030] (1) The guide positioning shaft of item 8, the first guide positioning sleeve of item 9, the second guide positioning sleeve of item 10, and the third guide positioning sleeve of item 11, which are coaxially installed with the rotor assembly of item 7, are clearance fits with the bearing housing of the front cover of item 5. The fit diameter is φ460mm and the fit clearance is 0.2mm. This ensures the coaxiality of the front end of the rotor assembly and the stator assembly. When the rotor assembly is axially advanced, although the unilateral magnetic pull of the motor increases continuously, the axial support span of the rotor decreases continuously. The support span of the entire rotor assembly, the guide positioning shaft of item 8, the first guide positioning sleeve of item 9, the second guide positioning sleeve of item 10, and the third guide positioning sleeve of item 11 continuously decreases and the rigidity continuously increases.

[0031] (2) The position of the mounting screw holes of the 12 guide positioning screws of item 3 is φ0.1. The fitting diameter of the 12 through holes on the rear end cover of item 3 and item 2 is φ31mm. The fitting is a clearance fit with a fitting clearance of 0.2mm. This ensures the coaxiality of the rear end of the rotor assembly and the stator assembly. The inlet end of item 3 is machined with a 5° guide angle to facilitate the introduction of item 3 into the rear end cover.

[0032] (3) Item 1 The L-type balancing hoist can adjust the fixed position of the slider according to the center of gravity of the rotor assembly, so that the rotor gravity is balanced and the rotor assembly is in a horizontal state after being lifted.

[0033] (4) When assembling a permanent magnet motor, there is an axial magnetic pull force. The balance of the four M30 magnetic pull balancing screws connected to the rear end cover of item 2 can move together with the rear end cover, which can ensure that the rotor assembly does not move axially during the assembly process. With the smooth transmission of the magnetic pull balancing screws, the rotor assembly can slowly enter the stator assembly until the stator assembly and rotor assembly are axially aligned.

[0034] Key technical points of the present invention: (1) Horizontal mounting scheme for high-power semi-direct drive permanent magnet synchronous motor;

[0035] (2) Measures to balance the axial magnetic pull when a high-power permanent magnet synchronous motor is horizontally mounted;

[0036] (3) Method for guiding and positioning the front and rear ends of a high-power semi-direct drive permanent magnet synchronous motor in a horizontal configuration.

Claims

1. A horizontal installation method of a high-power semi-direct-drive permanent magnet motor, characterized in that, It comprises the following steps: (1) installing a guide positioning shaft and a guide positioning sleeve assembly at the front end of the rotating shaft of the rotor assembly; the guide positioning sleeve assembly is sleeved on the outer periphery of the guide positioning shaft to thereby install the guide positioning shaft at the front end of the rotating shaft, and the guide positioning sleeve assembly extends into the bearing chamber of the front end cover and is in clearance fit with the bearing chamber; (2) after the rotor assembly and the rear end cover are assembled, the end of the rotating shaft extends out of the bearing chamber of the rear end cover, the extended part is lifted by the L-shaped balance lifting appliance to make the rotating shaft in a horizontal suspended state; the rear end cover is connected with the stator assembly through a plurality of guide positioning rods, the guide positioning rods are in clearance fit with a plurality of through holes arranged on the periphery of the rear end cover and are fixedly connected between the rear end cover, to ensure the coaxiality of the rear end of the rotor assembly and the stator assembly; (3) when the rear end cover and the rotor assembly move axially, the guide positioning rods move with the rear end cover and enter the through holes on the periphery of the rear end of the stator assembly, to ensure that the rotor assembly does not move axially during assembly, and with the stable movement of the guide positioning sleeve assembly and the guide positioning rods, the rotor assembly slowly enters the stator assembly along the axial direction, until the stator assembly and the rotor assembly are axially aligned, the bearings at the front end of the rotor assembly enter the bearing chamber, at this time, the guide sleeve assembly is disassembled, the front end cover of the rotor bearing is installed, and the installation of the rotor assembly is completed; In step (1), the guide sleeve assembly is composed of a first guide positioning sleeve, a second guide positioning sleeve and a third guide positioning sleeve; the end of the guide positioning shaft extends outward in the radial direction to form a flared section, the flared section is on the front end of the rotating shaft, the inner wall of the front end of the third guide positioning sleeve is in a constricted structure and the constricted structure is sleeved on the outer side and the front side of the flared section of the guide positioning shaft, the rest of the third guide positioning sleeve is sleeved on the periphery of the front end of the rotating shaft and closely attached to the front end surface of the rotating shaft bearing; the second guide positioning sleeve and the first guide positioning sleeve are sleeved on the guide positioning shaft in turn next to the third guide positioning sleeve; the clearance fit between the guide positioning sleeve and the bearing chamber of the front end cover is 0.2 mm; the guide positioning rod comprises a plurality of guide positioning screws and a plurality of magnetic force balance lead screws, the ends of the guide positioning screws and the magnetic force balance lead screws are respectively installed in the through holes of the rear end cover, and the front ends are inserted into the through holes on the periphery of the rear end of the stator assembly.

2. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 1, characterized in that, The position tolerance of the guide positioning screw is φ0.1, the fit diameter of the through hole on the rear end cover is φ31 mm, and the fit clearance is 0.2 mm.

3. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 1, characterized in that, There are 12 guide positioning screws, and the end part is processed with a guide angle of 5°.

4. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 1, characterized in that, There are 4 magnetic force balance lead screws.

5. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 4, characterized in that, The specification of the magnetic force balance lead screw is M30.

6. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 1, characterized in that, The L-shaped balance lifting appliance is turned by 90 degrees, a sliding block is movably arranged on the horizontal section of the L-shaped balance lifting appliance, the sliding block is connected with a lifting mechanism, a fixed sleeve is installed at the bottom of the vertical section, and the fixed sleeve is used for lifting the end of the rotating shaft.

7. The horizontal installation method of a high-power semi-direct-drive permanent magnet motor according to claim 6, characterized in that, The sliding block is positioned by a positioning screw and the L-shaped balance lifting appliance.

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