A bidirectional positioning assembly tool and method for a permanent magnet brushless DC high-speed motor

Abstract

The application relates to a bidirectional positioning assembly tool and method for a permanent magnet brushless DC high-speed motor, which comprises a guide shell, a fixed support disc, a guide shaft, a bearing mounting guide seat and a bearing mounting pressing column. The guide shell is matched with one side of the bottom of the fixed support disc, is used for matching the bearing pre-installed in the rotor end cover with the motor shaft of the rotor assembly, the bearing mounting guide seat is matched with the bearing mounting pressing column, is used for realizing the press fitting of the front bearing on the stator assembly, and the guide shaft, the guide shell and the fixed support disc are matched, and are used for realizing the assembly of the stator assembly body and the rotor assembly. The application solves the motor rotor bias problem, avoids the friction between the stator and the rotor and the surface damage of the stator and the rotor, can improve the bearing installation precision, guarantees the bearing installation quality, and improves the motor assembly efficiency.

Description

Technical Field

[0001] This invention belongs to the field of permanent magnet brushless motor assembly technology, and specifically relates to a bidirectional positioning assembly method for a permanent magnet brushless DC high-speed motor. Background Technology

[0002] Permanent magnet brushless DC high-speed motors have advantages such as high speed, high power density, small size, low noise, small moment of inertia, and fast dynamic response, which makes them widely used in aerospace, shipbuilding, automotive, home appliance and other fields. The demand is increasing day by day, and the permanent magnet brushless DC high-speed motor industry is developing rapidly.

[0003] Permanent magnet brushless DC high-speed motors typically employ two bearings at both ends of the motor shaft as a support structure to ensure normal motor operation. Current assembly methods involve installing one bearing in the stator bearing housing, then inserting the motor shaft (including the shaft itself) into the stator from one side, simultaneously threading the shaft through the bearing. Because the rotor contains permanent magnets, these magnets attract each other to the stator core during installation, causing the motor shaft to become misaligned. This not only affects the installation accuracy of the bearing at the other end but also generates radial loads on the bearing, potentially leading to bearing damage and directly impacting the motor's lifespan and reliability. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a bidirectional positioning assembly fixture and assembly method for a permanent magnet brushless DC high-speed motor that ensures the rotor does not become misaligned during motor assembly, guarantees bearing installation accuracy, and ensures reliable motor operation.

[0005] One of the above-mentioned objectives of the present invention is achieved by the following technical solution:

[0006] A bidirectional positioning assembly fixture for a permanent magnet brushless DC high-speed motor includes a guide housing, a fixed support plate, a guide shaft, a bearing mounting guide seat, and a bearing mounting pressure column.

[0007] The guide housing is a cylindrical housing with a bottom at one end. An inner central boss and a central through hole are provided at the bottom of the guide housing. The diameter of the central through hole is consistent with the outer diameter of the motor shaft used to install the rear bearing on the flange side. Multiple through holes are evenly distributed around the central boss at the bottom of the guide housing along the circumferential direction. An axial slot is provided on the side wall of the guide housing. The through holes and slots are used to realize the lead wire.

[0008] The fixed support plate is a disc with an inner cavity and a central hole at one end; the central hole on the fixed support plate is a stepped hole, consisting of a small-diameter screw through hole and a large-diameter shaft mounting hole, and the diameter of the shaft mounting hole is consistent with the outer diameter of the outermost shaft section on the flange side of the motor shaft.

[0009] The bearing mounting guide seat consists of a guide shaft and an end plate. One end of the guide shaft is perpendicularly inserted and fixedly connected to the center of the end plate. The diameter of the guide shaft is the same as the inner diameter of the front bearing of the motor. A clearance hole is provided on the side of the end plate near the protrusion of the guide shaft for the outer boss of the bearing seat of the stator assembly to be inserted.

[0010] The bearing mounting column is a hollow column with a central hole, consisting of a small-diameter guide hole section and a large-diameter clamping hole section; the diameter of the small-diameter guide hole section matches the outer diameter of the guide shaft of the bearing mounting guide seat, and the diameter of the large-diameter clamping hole section is greater than or equal to the inner diameter of the outer ring of the bearing.

[0011] The guide shaft comprises a central main shaft section, a small shaft diameter section at one end of the main shaft section, and a mating section at the other end of the main shaft section. The outer diameter of the main shaft section matches the inner diameter of the front bearing of the motor, the outer diameter of the small shaft diameter section matches the diameter of the reserved insertion hole at the end of the rotor shaft, and the mating section is used to make tight contact with the outer boss end of the bearing seat of the stator assembly to realize the assembly of the rotor assembly and the stator assembly.

[0012] The guide housing mates with the bottom side of the fixed support plate to mate the rear bearing, which is pre-installed in the rotor end cover, with the motor shaft of the rotor assembly; the bearing mounting guide seat mates with the bearing mounting pressure column to press the front bearing onto the stator assembly; the guide shaft, guide housing, and fixed support plate mate to assemble the stator assembly body and the rotor assembly.

[0013] The second objective of this invention is achieved through the following technical solution:

[0014] An assembly method based on the above-mentioned bidirectional positioning assembly fixture for a permanent magnet brushless DC high-speed motor is characterized by comprising the following steps:

[0015] Step 1: Place the motor stator assembly without bearings on the bearing mounting guide seat. Place the front bearing onto the guide shaft from the end furthest from the end plate, and slide it down the guide shaft to the bearing hole position at the front of the stator housing. Then, place the bearing mounting pin onto the guide shaft with the large-diameter clamping hole facing down, and press down the bearing mounting pin to press the front bearing into the bearing hole. Remove the bearing mounting guide seat and the bearing mounting pin to complete the front bearing installation.

[0016] Step 2: Install the rear bearing into the bearing hole of the end cover, tighten it with the bearing mounting pin, and limit it with the retaining ring;

[0017] Step 3: Insert the section of the motor shaft outside the flange into the bearing inner hole of the end cover, and insert it into the guide housing together. So that the end of the motor shaft outside the rear bearing passes through the center hole of the guide housing and the center hole of the fixed support plate in sequence. Then, install the fixing screw through the hole of the small diameter screw of the fixed support plate. The fixing screw forms a threaded connection with the threaded hole of the section of the motor shaft to realize the installation of the rear bearing.

[0018] Step 4: Insert the guide shaft through the front end of the stator assembly, press the guide shaft's contact section against the outer convex surface of the bearing housing, and place it stably on the worktable with the contact end facing down.

[0019] Step 5: Assemble the stator and rotor assemblies:

[0020] 5.1 Align the assembled structure from step 3 with the end furthest from the front bearing facing down with the assembled structure from step 4, so that the insertion hole at the end of the motor shaft and the small diameter section of the guide shaft form an insertion positioning fit.

[0021] 5.2. Lay down the combined structure from step 5.1, and gradually push the rotor assembly toward the stator assembly along the axial direction. At the same time, gradually pull the guide shaft outward so that the guide housing fits onto the outer circle of the stator until the motor shaft is successfully installed into the front bearing of the stator housing. The guide shaft is then completely pulled out, and the end cover clamping ring is installed on the stator housing.

[0022] 5.3 Remove the fixing screws, fixing support plate, and guide housing. At the same time, use screws to fix the end cover clamping ring to the stator housing to complete the bidirectional positioning installation of the motor.

[0023] The advantages and positive effects of this invention are as follows:

[0024] 1. This invention achieves the positioning and installation of the front bearing on the motor through the cooperation of the bearing mounting guide seat and the bearing mounting pressure column. After the rear bearing is installed on the end cover, the positioning and installation of the rear bearing on the motor is achieved through the cooperation of the guide housing and the fixed support plate. The positioning and installation of the rotor assembly and the stator assembly are achieved through the cooperation of the guide housing and the guide shaft. This solves the problem of motor rotor misalignment, avoids stator-rotor friction and damage to the stator-rotor surfaces, and also avoids the generation of excess material that contaminates the bearing.

[0025] 2. The guide shaft and motor shaft of this invention are connected by a plug-in fit, which is simple to disassemble and assemble, facilitates the replacement of the guide shaft, effectively extends the service life of the device, and reduces the processing cost;

[0026] 3. This invention can improve bearing installation accuracy and ensure bearing installation quality; it can also improve motor assembly efficiency and promote the advancement of motor assembly technology. Attached Figure Description

[0027] Figure 1 These are schematic diagrams of the guide housing of the present invention: 1a, sectional view, 1b, left view;

[0028] Figure 2 This is a schematic diagram of the fixed support plate of the present invention, 2a, front view, 2b, sectional view;

[0029] Figure 3 This is a schematic diagram of the bearing mounting guide seat of the present invention;

[0030] Figure 4 These are schematic diagrams of the bearing mounting pressure column of the present invention, 4a, front view, and 4b, sectional view;

[0031] Figure 5 This is a schematic diagram of the structure of the guide shaft of the present invention;

[0032] Figure 6 This is a schematic diagram of the rotor assembly of the present invention;

[0033] Figure 7 This is a schematic diagram of the stator assembly of the present invention;

[0034] Figure 8 This is a schematic diagram of the front bearing being installed in the stator assembly of the present invention;

[0035] Figure 9 This is a schematic diagram of the rear bearing of the present invention installed inside the end cover;

[0036] Figure 10 This is a reference diagram showing the rear bearing of the present invention mounted on the rotor assembly;

[0037] Figure 11 This is a reference diagram of the guide shaft of the present invention passing through the stator assembly;

[0038] Figure 12 This is a reference diagram of the stator assembly and rotor assembly after they have been assembled in place (without removing the auxiliary tooling);

[0039] Figure 13 This is an assembly diagram of the stator and rotor of the present invention. Detailed Implementation

[0040] The structure of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that these embodiments are descriptive and not limiting.

[0041] A bidirectional positioning and assembly method for a permanent magnet brushless DC high-speed motor, please refer to [link / reference]. Figures 1-13 The auxiliary tooling used in this assembly method includes a guide housing, a fixed support plate, a guide shaft, a bearing mounting guide seat, and a bearing mounting pressure column.

[0042] The guide housing is a cylindrical housing with a bottom at one end. An inner central boss 1.1 and a central through hole 1.2 are provided at the bottom of the guide housing. The diameter of the central through hole is consistent with the outer diameter of the bearing mounting shaft on the flange side of the motor shaft. Four through holes 1.3 are evenly distributed circumferentially around the central boss at the bottom of the guide housing. An axial slot 1.4 is provided on the side wall of the guide housing to facilitate the assembly of motors with side-leading or end-leading winding structures, and to avoid damage to the motor leads 500.

[0043] The fixed support plate is a disc with an inner cavity 2.1 and a central hole at one end. The outer diameter of the fixed support plate is the same as that of the guide housing. The central hole on the fixed disc is a stepped hole, consisting of a small-diameter screw passing through hole 2.2 and a large-diameter shaft mounting hole 2.3. The shaft mounting hole is located on the side closest to the inner cavity of the fixed support plate. The diameter of the shaft mounting hole is the same as the outer diameter of the outermost end of the motor shaft flange side. Furthermore, four threaded holes 2.4 are evenly distributed in a square pattern around the periphery of the central hole on the fixed support plate for installing tightening screws to achieve tight clamping between the fixed support plate and the guide housing.

[0044] The guide housing mates with the bottom side of the fixed support plate to allow the rear bearing, which is pre-installed in the rotor end cover, to mate with the motor shaft.

[0045] The bearing mounting guide seat 3 consists of a guide shaft 3.1 and an end plate 3.2. One end of the guide shaft is perpendicularly inserted and fixedly connected to the center of the end plate. The diameter of the guide shaft is the same as the inner diameter of the front bearing in the bearing housing of the stator assembly, and it is used to guide the installation of the bearing. A clearance hole 3.2.1 is provided on the side of the end plate near the protrusion of the guide shaft. The diameter of the clearance hole matches the size of the outer boss of the bearing housing of the stator assembly, so that the outer boss is embedded in the clearance hole when the bearing is installed.

[0046] The bearing mounting pin 4 is used to press the bearing into a set position when mounting bearings on the rotor shaft and stator assembly. The bearing mounting pin is a hollow pin with a central hole. This central hole consists of a small-diameter guide hole section 4.1 and a large-diameter clamping hole section 4.2. The diameter of the small-diameter guide hole section is designed to have a clearance fit with the outer diameter of the guide shaft of the bearing mounting guide seat, ensuring a guiding fit between the bearing mounting pin and the bearing mounting guide seat. The diameter of the large-diameter clamping hole section is greater than or equal to the inner diameter of the bearing's outer ring. The end face of the large-diameter clamping hole section presses against the outer ring of the bearing, achieving press-fitting of the bearing.

[0047] The guide shaft 5 is used to guide and support the stator assembly during the assembly of the stator assembly and the rotor assembly. The guide shaft consists of a central main shaft section 5.2, a small-diameter section 5.1 located at one end of the main shaft section, and a mating section 5.3 located at the other end of the main shaft section. The outer diameter of the main shaft section matches the inner diameter of the bearing mounted on the stator assembly, and the outer diameter of the small-diameter section matches the diameter of the reserved insertion hole at the end of the rotor shaft. The mating section is used to make tight contact with the outer boss end of the bearing seat of the stator assembly to realize the assembly of the rotor and the stator.

[0048] The bearing mounting guide seat and bearing mounting pressure column cooperate to press-fit the front bearing onto the stator assembly. The guide shaft, guide housing, and fixed support plate cooperate to assemble the stator assembly body and the rotor assembly.

[0049] A bidirectional positioning and assembly method for a permanent magnet brushless DC high-speed motor based on the above-mentioned auxiliary tooling, see [link to documentation]. Figures 6-13 It includes the following steps:

[0050] Step 1: Install the bearing in the stator assembly: Place the motor stator assembly without bearings on the bearing mounting guide seat. Place the front bearing onto the guide shaft from the end furthest from the end plate, and slide it down the guide shaft to the bearing hole position at the front of the stator housing. Then, place the bearing mounting pin onto the guide shaft with the large-diameter clamping hole facing down, and press down the bearing mounting pin to press the front bearing into the bearing hole. Remove the bearing mounting guide seat and the bearing mounting pin to complete the installation of the front bearing 300.

[0051] Step 2: Install the rear bearing 400 into the bearing hole of the end cover 105, press it with the bearing mounting pin, and limit it with the retaining ring 106;

[0052] Step 3: Install the rear bearing onto the motor shaft of the rotor assembly 100 (mainly composed of motor shaft 104, rotor magnet 103, and Hall magnet 102, with the Hall magnet mounted on the flange 101 of the motor shaft). Specifically: insert the shaft section outside the flange side of the motor shaft into the bearing inner hole of the end cover, and together with it, insert it into the guide housing. So that the shaft end of the motor shaft located outside the rear bearing passes through the center hole of the guide housing and the center hole of the fixed support plate in sequence. Then, install the fixing screw in the hole through which the small-diameter screw of the fixed support plate passes. The fixing screw forms a threaded connection with the threaded hole of the section of the motor shaft, thereby realizing the installation of the rear bearing.

[0053] Step 4: Insert the guide shaft through the front end of the stator assembly 200 (which is mainly composed of the stator body 203, stator housing 202, and flange 201, with a bearing seat 204 on the stator housing for mounting the front bearing), so that the contact section on the guide shaft is pressed tightly against the outer convex surface of the bearing seat, and place it stably on the worktable with the contact end facing down.

[0054] Step 5: Assemble the stator and rotor assemblies:

[0055] 5.1 Align the assembled structure from step 3 with the end furthest from the front bearing facing down with the assembled structure from step 4, so that the insertion hole at the end of the motor shaft and the small diameter section of the guide shaft form an insertion positioning fit.

[0056] 5.2. Lay down the combined structure from step 5.1, and gradually push the rotor assembly toward the stator assembly along the axial direction. At the same time, gradually withdraw the guide shaft so that the guide housing fits onto the outer circle of the stator until the motor shaft is successfully installed into the front bearing of the stator housing. The guide shaft is completely withdrawn, and the end cover clamping ring 205 is installed on the stator housing.

[0057] 5.3 Remove the fixing screws, fixing support plate, and guide housing. At the same time, use screw 206 to fix the end cover clamping ring to the stator housing to complete the bidirectional positioning installation of the motor.

[0058] Although embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A bidirectional positioning assembly fixture for a permanent magnet brushless DC high-speed motor, characterized in that: Includes guide housing, fixed support plate, guide shaft, bearing mounting guide seat, and bearing mounting pressure column; The guide housing is a cylindrical housing with a bottom at one end. An inner central boss and a central through hole are provided at the bottom of the guide housing. The diameter of the central through hole is consistent with the outer diameter of the motor shaft used to install the rear bearing on the flange side. Multiple through holes are evenly distributed around the central boss at the bottom of the guide housing along the circumferential direction. An axial slot is provided on the side wall of the guide housing. The through holes and slots are used to realize the lead wire. The fixed support plate is a disc with an inner cavity and a central hole at one end; the central hole on the fixed support plate is a stepped hole, consisting of a small-diameter screw through hole and a large-diameter shaft mounting hole, and the diameter of the shaft mounting hole is consistent with the outer diameter of the outermost shaft section on the flange side of the motor shaft. The bearing mounting guide seat consists of a guide shaft and an end plate. One end of the guide shaft is perpendicularly inserted and fixedly connected to the center of the end plate. The diameter of the guide shaft is the same as the inner diameter of the front bearing of the motor. A clearance hole is provided on the side of the end plate near the protrusion of the guide shaft for the outer boss of the bearing seat of the stator assembly to be inserted. The bearing mounting column is a hollow column with a central hole, consisting of a small-diameter guide hole section and a large-diameter clamping hole section; the diameter of the small-diameter guide hole section matches the outer diameter of the guide shaft of the bearing mounting guide seat, and the diameter of the large-diameter clamping hole section is greater than or equal to the inner diameter of the outer ring of the bearing. The guide shaft comprises a central main shaft section, a small shaft diameter section at one end of the main shaft section, and a mating section at the other end of the main shaft section. The outer diameter of the main shaft section matches the inner diameter of the front bearing of the motor, the outer diameter of the small shaft diameter section matches the diameter of the reserved insertion hole at the end of the rotor shaft, and the mating section is used to make tight contact with the outer boss end of the bearing seat of the stator assembly to realize the assembly of the rotor assembly and the stator assembly. The guide housing mates with the bottom side of the fixed support plate to mate the rear bearing, which is pre-installed in the rotor end cover, with the motor shaft of the rotor assembly; the bearing mounting guide seat mates with the bearing mounting pressure column to press the front bearing onto the stator assembly; the guide shaft, guide housing, and fixed support plate mate to assemble the stator assembly body and the rotor assembly.

2. An assembly method based on the bidirectional positioning assembly fixture for a permanent magnet brushless DC high-speed motor as described in claim 1, characterized in that, Includes the following steps: Step 1: Place the motor stator assembly without bearings on the bearing mounting guide seat. Place the front bearing onto the guide shaft from the end furthest from the end plate, and slide it down the guide shaft to the bearing hole position at the front of the stator housing. Then, place the bearing mounting pin onto the guide shaft with the large-diameter clamping hole facing down, and press down the bearing mounting pin to press the front bearing into the bearing hole. Remove the bearing mounting guide seat and the bearing mounting pin to complete the front bearing installation. Step 2: Install the rear bearing into the bearing hole of the end cover, tighten it with the bearing mounting pin, and limit it with the retaining ring; Step 3: Insert the section of the motor shaft outside the flange into the bearing inner hole of the end cover, and insert it into the guide housing together. So that the end of the motor shaft outside the rear bearing passes through the central through hole of the guide housing and the central hole of the fixed support plate in sequence. Then, install the fixing screw in the hole through which the small diameter screw of the fixed support plate passes. The fixing screw forms a threaded connection with the threaded hole of the section of the motor shaft to realize the installation of the rear bearing. Step 4: Insert the guide shaft through the front end of the stator assembly, press the guide shaft's contact section against the outer convex surface of the bearing housing, and place it stably on the worktable with the contact end facing down. Step 5: Assemble the stator and rotor assemblies: 5.1 Align the assembled structure from step 3 with the end furthest from the front bearing facing down with the assembled structure from step 4, so that the insertion hole at the end of the motor shaft and the small diameter section of the guide shaft form an insertion positioning fit. 5.

2. Lay down the combined structure from step 5.1, and gradually push the rotor assembly toward the stator assembly along the axial direction. At the same time, gradually pull the guide shaft forward so that the guide housing fits onto the outer circle of the stator until the motor shaft is successfully installed into the front bearing of the stator housing. The guide shaft is then completely pulled out, and the end cover clamping ring is installed on the stator housing. 5.3 Remove the fixing screws, fixing support plate, and guide housing. At the same time, use screws to fix the end cover clamping ring to the stator housing to complete the bidirectional positioning installation of the motor.

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