A half-direct-drive rotor assembly method with a skew key locking structure

Abstract

The application provides an assembly method of a key locking structure semi-direct drive rotor, and belongs to the field of motor manufacturing, which comprises the following steps: fixing a rotor support, a transmission flange and an extreme mounting dummy shaft by fastening bolts; fixing the extreme mounting dummy shaft on a magnetic pole mounting platform and installing the magnetic poles in the dovetail groove of the rotor support; after installing the process fixing keys between the dovetail groove of the rotor support and the magnetic poles, installing the adjacent magnetic poles; after installing all the magnetic poles, removing the process fixing keys, installing the inclined keys, trimming the excess inclined key part, removing the extreme mounting dummy shaft from the rotor with trimmed inclined keys, installing a dynamic balance dummy shaft in the inner hole of the transmission flange, and performing dynamic balance correction. The operation method is simple and convenient, the rotor magnetic poles are fixed firmly, the stability of operation is improved, the failure rate of the rotor magnetic poles is reduced, and the service life of the motor is prolonged.

Description

Technical Field

[0001] This invention provides an assembly method for a key-locking structure semi-direct drive rotor, belonging to the field of motor manufacturing. Background Technology

[0002] "Dual carbon" is an important goal of my country's green and low-carbon development, which can bring multiple benefits to environmental quality and industrial development. With the inclination of national economic policies, the wind power industry has ushered in revolutionary development. Vigorously developing wind power is conducive to promoting the green transformation of the economy and accelerating the formation of green production methods. Semi-direct drive wind power has become the new favorite in the wind power industry due to its unparalleled advantages.

[0003] With the development of semi-direct drive technology and the demands of economic growth, the installed capacity of semi-direct drive motors with higher single-unit capacity is increasing. As competition intensifies, lower-cost, higher-speed semi-direct drive motors are gaining market favor. The biggest manufacturing challenge for this type of semi-direct drive motor is the poor stability of the rotor operation. Increasing the speed reduces rotor safety, and the failure rate, especially the failure rate of the rotor magnetic poles, increases significantly. To improve rotor magnetic pole stability, traditional bolt-locking methods are no longer sufficient, as bolt breakage is highly likely. Therefore, this type of motor uses a dovetail connection structure to fix the magnetic poles to the rotor support, employing paired wedge keys for single-sided locking to secure the magnetic poles, achieving a reliable connection between the rotor magnetic poles and the rotor support.

[0004] The aforementioned key is extremely thin and has poor rigidity. Conventional keying processes easily cause premature bending and deformation, resulting in a small tension area between the magnetic pole and the rotor support, and insufficient magnetic pole tension. During high-speed rotation, the magnetic pole is prone to loosening due to the combined effects of centrifugal force and motor heat, affecting the rotor's operational stability. Simultaneously, the rotor contains numerous magnets with strong attraction. Traditional keying, key cutting, and other component assembly processes become extremely difficult under the presence of these strong magnets. Ensuring effective locking of the magnetic poles, effective fixation of the key, and reliable fixation of other components, thereby guaranteeing the stability of the magnetic poles during high-speed rotor rotation, becomes a significant challenge. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned shortcomings and provide an assembly method for a key-locking structure semi-direct drive rotor. The rotor magnetic poles produced by this method are firmly fixed, which improves the stability of semi-direct drive rotor operation and extends the service life of the motor.

[0006] According to the technical solution provided by the present invention, a method for assembling a semi-direct drive rotor with a keyed locking structure includes the following steps:

[0007] 1) The rotor support and the transmission flange are connected by bolts, and the connected transmission flange and the pole mounting dummy shaft are fixed together by fastening bolts;

[0008] 2) Fix the pole-mounting dummy shaft from step 1) onto the magnetic pole mounting platform, and install the magnetic poles in the dovetail groove of the rotor bracket;

[0009] 3) After installing the process fixing key between the dovetail groove of the rotor support and the magnetic pole in step 2), install the adjacent magnetic pole;

[0010] 4) After all magnetic poles are installed, remove the process fixing key and install the bevel key;

[0011] 5) Trim any excess key edges;

[0012] 6) After the rotor with the key has been repaired, remove the pole dummy shaft, install the dynamic balance dummy shaft into the inner hole of the transmission flange, and perform dynamic balance correction.

[0013] As a further improvement of the present invention, in step 2), the method of installing the magnetic pole is as follows: adjust the position of the rotor support, align the dovetail groove on the rotor support with the magnetic pole mounting groove, place the magnetic pole box into the magnetic pole mounting groove, connect them in series with square screws, install the magnetic pole pressure plate on the side of the magnetic pole box and apply thread locking agent to tighten it to form the magnetic pole, and then push the magnetic pole into the dovetail groove through the hydraulic cylinder.

[0014] As a further improvement of the present invention, the method for removing the process fixing key in step 4) is: to push out the process fixing key by using a process tapping key and a hammer.

[0015] As a further improvement of the present invention, the slant key in step 4) includes two connected key plates, and the connection between the two key plates is provided with a mutually cooperating slant structure.

[0016] As a further improvement of the present invention, the method for installing the slanted key in step 4) is as follows:

[0017] 1) Tap the two key pieces into the pigeon tail grooves from both ends until the two key pieces connect to form a diagonal key;

[0018] 2) Place the rotor with the inclined key installed into an oven and heat it at a temperature not exceeding 70 degrees Celsius;

[0019] 3) Immediately after removing the rotor, tap the two key plates. Before tapping, the slanted key sleeves must be put on.

[0020] 4) After the rotor has cooled to room temperature, tap the two key plates again.

[0021] As a further improvement of the present invention, in the key trimming step of step 5), a cutting protective sleeve needs to be put on the rotor before trimming.

[0022] As a further improvement of the present invention, after the oblique key is trimmed in step 5), the oblique key and the transmission flange connection part need to be fixed by spot welding.

[0023] As a further improvement of the present invention, the installation depth of the process fixing key in step 2) is 1 / 3 of the depth of the pigeon tail groove.

[0024] The beneficial effects of this invention are as follows:

[0025] The operation is simple and convenient, the rotor magnetic poles are firmly fixed, improving the stability of operation, reducing the failure rate of rotor magnetic poles, and extending the service life of the motor. Attached Figure Description

[0026] Figure 1 This is a diagram showing the positional relationship between the rotor support, magnetic poles, and inclined key of the present invention.

[0027] Figure 2 This is a rotor assembly diagram of the present invention.

[0028] Figure 3 for Figure 2 A sectional view along line AA.

[0029] Figure 4 This is a schematic diagram of the magnetic pole mounting platform of the present invention.

[0030] Figure 5 , Figure 6 This is a schematic diagram of the magnetic poles of the present invention.

[0031] Figure 7 This is a schematic diagram of the process fixing key of the present invention.

[0032] Figure 8 The process of this invention involves striking a key.

[0033] Figure 9 Cutting protective sleeve of the present invention

[0034] Figure 10 Protective sleeve for the slant key of this invention

[0035] Figure 11 This is a schematic diagram of the oblique key of the present invention.

[0036] Figure 12 This is a schematic diagram of the dummy axis for dynamic balancing in this invention.

[0037] Explanation of reference numerals in the attached drawings: 1. Rotor support; 2. Transmission flange; 3. Bolt; 4. Pole mounting dummy shaft; 5. Magnetic pole assembly platform; 6. Dovetail groove; 7. Magnetic pole box; 8. Magnetic pole mounting slot; 9. Square screw; 10. Hydraulic cylinder; 11. Magnetic pole pressure plate; 12. Magnetic pole; 13. Process fixing key; 14. Angled key; 15. Process striking key; 16. Angled key protective sleeve; 17. Cutting protective sleeve; 18. Dynamic balancing dummy shaft. Detailed Implementation

[0038] The present invention will now be further described with reference to the embodiments shown in the accompanying drawings:

[0039] The main assembly methods of this invention are all based on the manufacturing process surrounding the inclined key 14, and the operation steps are as follows:

[0040] Lift the rotor bracket 1 and turn it over so that the 20-M27 threaded holes face upwards. Place it upright on a platform with a square hole. Use two M27 eye bolts to lift the transmission flange 2 and install it onto the rotor bracket 1. The rotor bracket 1 and the transmission flange 2 are connected using bolts 3. Apply molybdenum disulfide lubricant to the threads of the bolts 3. Note that you should first tighten all bolts 3 symmetrically with a cross-shaped torque of 50%, and then tighten all bolts 3 symmetrically with a cross-shaped torque of 100%. After confirming that all bolts 3 are tightened, mark the anti-loosening line. Using a cross-shaped symmetrical tightening of the bolts 3 ensures that the transmission flange is evenly compressed, reducing workpiece deformation and internal stress caused by installation eccentricity. Tightening the torque in two steps can effectively reduce the torque attenuation after a single tightening. All of the above measures make the transmission flange 2 more effectively and reliably fixed.

[0041] Insert the dummy pole shaft 4 into the inner hole of the transmission flange 2, then assemble the dummy pole shaft 4 and the transmission flange 2 together. Tighten all connecting bolts to the torque shown in the drawing, using a cross-shaped diagonal tightening method. Use a lifting tool to lift the dummy pole shaft 4 and rotate it 90° until it is horizontal. Lift the rotor bracket with the dummy pole shaft 4 installed onto the magnetic pole mounting platform 5, ready to install the magnetic pole 12.

[0042] The non-drive flange end of rotor support 1 is close to the magnetic pole assembly platform 5. On the non-flange end of rotor support 1, the pigeon tail grooves are numbered N1, S1, N2, S2, N3, S3, N4, S4, N5, and S5 in a clockwise direction.

[0043] Check whether the magnets in each magnetic pole box 7 protrude from both ends of the iron core. If there are protrusions, it is strictly forbidden to use them. Use a polarity pen to check the polarity of each magnetic pole box 7 of the rotor.

[0044] Place the magnetic pole pressure plate 11 into the magnetic pole mounting slot 8 on the magnetic pole mounting platform 5, install and fix the square screw 9, place the rotor magnetic pole box 7 with polarity N into the magnetic pole mounting slot 8, align the magnetic pole box 7 with the square screw 9 and insert it, install the magnetic pole pressure plate 11 and apply thread locking agent to tighten it to form the magnetic pole 12, use the hydraulic cylinder 10 to push the rotor magnetic pole box 7 to the bottom, and continue to operate in this way according to the quantity required by the drawing. Make the N1 mark on the surface of the magnetic pole 12.

[0045] The magnetic pole 12 is pushed into the dovetail groove 6 of the rotor bracket using the hydraulic cylinder 10 on the magnetic pole mounting platform 5. Due to the limited gap between adjacent magnetic poles 12, a fixing key 13 is used to limit the movement within each dovetail groove, ensuring that the magnetic pole 12 must be fixed to one side to guarantee smooth assembly of adjacent magnetic poles, while preventing the oblique key 14 from bending or being damaged during pole installation. The fixing key 13 is made as a flat key, with a thickness 0.3-0.4mm smaller than the mating gap of the dovetail 6, achieving both fixation and easy removal without damaging the mating surface of the dovetail. The fixing key 13 is driven into the rotor bracket from the drive flange end using a small hammer to limit the movement of one side of the magnetic pole 12. The N1, S1, N2, S2, N3, S3, N4, S4, N5, and S5 magnetic poles 12 are assembled sequentially according to the above method. The remaining magnetic poles 12 are then pushed into the dovetail groove 6 of the rotor bracket for fixation. The installation sequence is clockwise when viewed from the non-flange end.

[0046] The rotor is hoisted onto the roller shelf in preparation for the installation of the mortise key 14. The installation steps for mortise key 14 are: key repair --- initial cold hammering --- hot hammering --- second cold hammering. Hammering the mortise key is further divided into hammering with a small hammer and hammering with a large hammer, specifically as follows:

[0047] Before installation, the bevel keys 14 need to be inspected and repaired to achieve better contact and locking effect. Clean the surface of the bevel keys 14, ensuring the surface roughness of the mating surfaces is at least Ra1.6. Use sandpaper to polish the chamfers on both sides of the mating surfaces of the bevel keys 14, ensuring there are no burrs or bumps. Stack the mating surfaces of the bevel keys 14 together on a platform and check the gap, ensuring it is ≤0.05mm. Appropriately polish the ends of the bevel keys 14, ensuring no burrs remain, as this will affect the tightening effect. Only repaired and qualified bevel keys 14 can be used.

[0048] Insert the process striking key 15 into the non-flange end of the rotor support, and use a small hammer to push out the process fixing key 13. After the process fixing key 13 is pushed out, the process striking key 15 can be directly pulled out from the pigeon tail groove 6. If the oblique key 14 is too long, its rigidity is poor. When striking the key, the hammer is prone to missing the target due to the vibration of the oblique key 14, causing the oblique key to bend prematurely. If the oblique key 14 is too short, the safety distance is small, and when striking the key, the hammer is prone to missing the target, which may damage the magnetic pole 12 and other component surfaces. Therefore, the paired oblique keys 14 are inserted from both ends of the rotor support, and the exposed length of the oblique keys 14 is as close as possible to avoid one end being too long and having poor rigidity, which may cause bending, and the other end being too short, which may cause damage to other components due to insufficient safety distance.

[0049] Use a small hammer to gently tap the inclined keys 14 at both ends of the rotor support alternately. When the inclined keys 14 no longer have significant displacement, switch to a large hammer to strike them. Before using the large hammer, install the inclined key protective sleeve 16 on the inclined keys 14 to prevent excessive vibration caused by insufficient rigidity of the inclined keys 14 during striking, which could lead to the hammer hitting the wrong spot or the inclined keys bending prematurely, resulting in poor locking effect of the inclined keys 14. Use this method to strike the keys until the inclined keys 14 are tightened. Use the above method to replace all process fixing keys 13 in sequence.

[0050] After all the oblique keys 14 are installed, place the entire rotor into the oven for heating at 70℃. Do not exceed this temperature to avoid demagnetizing the magnets. After the rotor is removed from the oven, use a sledgehammer to perform a hot-pressing operation while it is still hot. When pressing the keys, alternate between both ends of the rotor support. Use the oblique key protective sleeve 16 during the pressing process. After heating, the pigeon tail groove 6 will expand beyond the pigeon tail. At this point, the oblique keys can be further tightened, resulting in a larger contact area between oblique keys, between oblique keys 14 and the pigeon tail, and between oblique keys 14 and the pigeon tail groove, thus achieving more thorough tightening.

[0051] After the rotor cools to room temperature, keying is performed again. A sledgehammer is used during keying, alternating between both ends of the rotor support. A beveled key protector (16) is required during keying. This hammering improves the distribution of restraint stress generated during hot keying and reduces the significant localized assembly stress caused by minor key deformation during hot keying.

[0052] After tightening the key 14 at the non-drive flange end of rotor bracket 1, cut off the excess key with a cutting machine. Before cutting, take precautions to prevent iron filings from adhering to the outer circumference of the rotor. Before cutting the key 14, install cutting protective sleeves 17 at both ends of the magnetic poles to prevent the cutting machine from being attracted by the strong magnetic field during cutting, which could lead to unstable machine control and a safety accident caused by the cutting blade colliding with the magnetic pole. The cut surface of the key 14 needs to be ground smooth. At the non-flange end of rotor bracket 1, ensure that the cut key is not higher than the end face of the rotor bracket. Then cover it with an end cover plate and tighten the fixing screws. Apply thread-locking agent to the screws before installation. The end of the key at the drive flange 2 end of rotor bracket 1 needs to extend 2cm above the drive flange end face. Spot weld the key plates at the drive flange end for fixation, and then weld the key 14 firmly to the drive flange 2 position. Spray paint the outer circumference and end face of the rotor magnetic poles for rust prevention.

[0053] Rotate the rotor 90° with the flange end facing upwards and place it on the dummy shaft mounting / removing frame. Remove the pole-mounted dummy shaft 4, and install the dynamic balancing dummy shaft 18 on the transmission flange before balancing it on the dynamic balancing machine. The dynamic balancing dummy shaft 18 requires high machining precision, with a single-sided clearance of 0-0.05mm between it and the transmission flange 2, which must be much smaller than the 0.05-0.11mm clearance between the pole-mounted dummy shaft 4 and the transmission flange 2. This avoids poor dynamic balancing accuracy caused by the clearance between the dynamic balancing dummy shaft 18 and the transmission flange 2. The dynamic balancing dummy shaft 18 and the pole-mounted dummy shaft 4 are fixed using different stop surfaces on the transmission flange 2 to avoid damage to the stop surface caused by the pole-mounted dummy shaft 4 during use, thus affecting the dynamic balancing accuracy. Using the pole-mounted dummy shaft 4 and the dynamic balancing dummy shaft 18 separately also reduces the probability of damage to the dynamic balancing dummy shaft 18 after long-term use. The counterweight position of the balance block is on the inner circular surface of the rotor support 1. Before welding the balance block, the paint at the corresponding welding position must be sanded clean and vacuumed. After the rotor dynamic balancing test, the quality of the counterweight welds must be checked and the paint must be touched up. The rotor manufacturing is then complete.

Claims

1. A method for assembling a half direct drive rotor with a skew key locking structure, characterized in that, Includes the following steps: Step 1) The rotor support (1) and the transmission flange (2) are connected by bolts (3). The connected transmission flange (2) and the pole mounting dummy shaft (4) are then fixed together by fastening bolts. Step 2) Fix the pole mounting dummy shaft (4) from Step 1) onto the magnetic pole mounting platform (5), and install the magnetic pole (12) in the dovetail groove (6) of the rotor bracket (1); Step 3) After installing the process fixing key (13) between the dovetail groove (6) and the magnetic pole (12) of the rotor support (1) in step 2), install the adjacent magnetic poles (12) in a clockwise direction. Step 4) After all the magnetic poles (12) are installed, remove the process fixing key (13) and install the slant key (14); Step 5) Trim the excess slant key (14); Step 6) After the rotor with the key (14) is repaired, remove the pole dummy shaft (4) and install the dynamic balance dummy shaft (18) in the inner hole of the transmission flange (2) for dynamic balance correction. The installation method of the slant key (14) in step 4) is as follows: 1) Tap the two key pieces into the pigeon tail groove (6) from both ends until the two key pieces are connected to form a diagonal key (14); 2) Place the rotor with the inclined key (14) installed into the oven and heat it at a temperature not exceeding 70 degrees Celsius; 3) After removing the rotor, immediately strike the two key plates. Before striking, the oblique key sleeve (16) must be put on. 4) After the rotor has cooled to room temperature, tap the two key plates again.

2. A method of assembling a half direct drive rotor according to claim 1, wherein In step 2), the installation method of the magnetic pole (12) is as follows: adjust the position of the rotor support (1), align the dovetail groove (6) on the rotor support (1) with the magnetic pole mounting groove (8), put the magnetic pole box (7) into the magnetic pole mounting groove (8), connect them in series with square screws (9), install the magnetic pole pressure plate (11) on the side of the magnetic pole box (7) and apply thread locking agent to tighten it to form the magnetic pole (12), and then push the magnetic pole (12) into the dovetail groove (6) through the hydraulic cylinder (10).

3. A method of assembling a half direct drive rotor according to claim 1, wherein The method for removing the process fixing key (13) in step 4) is as follows: the process fixing key (13) is pushed out by the process striking key (15) and the hammer.

4. A method of assembling a half direct drive rotor according to claim 1, wherein In step 4), the slant key (14) includes two connected key plates, and the connection between the two key plates is provided with a mutually cooperating slant structure.

5. A method of assembling a skew key locking structure half direct drive rotor as claimed in claim 1, wherein, In step 5), the key (14) trimming step requires the cutting protective sleeve (17) to be put on the rotor before trimming.

6. A method of assembling a skew key locking structure half direct drive rotor as claimed in claim 1, wherein, After the oblique key (14) in step 5) is trimmed, the oblique key (14) and the transmission flange (2) need to be fixed by welding.

7. A method of assembling a half direct drive rotor according to claim 1, wherein In step 3), the installation depth of the process fixing key (13) installed between the pigeon tail groove (6) and the magnetic pole (12) is more than 1 / 2 of the depth of the pigeon tail groove (6).

Images