A method of connecting a motor stator to a reducer housing

Abstract

The application discloses a connecting method of a motor stator and a reducer accommodating device, and comprises the following steps: providing a motor stator in the shape of a barrel and with a second end part; the reducer accommodating device is provided with a small-diameter cavity section and a bowl-shaped connecting structure at one end of the small-diameter cavity section; the peripheral wall of the bowl-shaped connecting structure is provided with a plurality of first through holes, and the bottom surface is provided with a plurality of second blind holes; embedding the second end part into the small-diameter cavity section, so that the second end part partially covers the second blind holes, and the covering area is greater than 50% of the opening area of each second blind hole; plugging the first through holes and only leaving two as glue injection holes and exhaust holes; injecting glue through the glue injection holes, so that the glue fills the gap between the bottom surface of the bowl-shaped connecting structure and the second end part and the second blind holes; solidifying the glue, and completing the connection. The method does not need to process screw holes on the stator, does not damage the structural strength of the stator, has high filling efficiency, low bubble residual rate, high connection strength, and can meet the strict use requirements of a robot joint.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, and in particular relates to a method for connecting a motor stator and a reducer housing. Background Technology

[0002] In robot joint modules, the connection between the motor stator and the reducer housing needs to simultaneously meet the requirements of high connection strength, high assembly precision, and high production efficiency.

[0003] Currently, the connection between the stator and the housing is mainly achieved by bolt fastening or interference fit. Bolted connections require machining threaded holes at the ends of the stator, which is a complex process and weakens the structural strength of the stator. Interference fit requires extremely high dimensional accuracy of the mating surfaces, resulting in stress concentration during assembly and making the stator prone to fretting wear and loosening over long-term use.

[0004] Adhesive bonding can avoid the above problems, but existing adhesive bonding processes generally suffer from defects such as insufficient filling of blind holes, excessive air bubbles, and uneven adhesive layer distribution. For example, if the stator end face is completely covered by blind holes, the adhesive cannot penetrate into the blind holes; if it is not covered at all, an effective anchoring structure cannot be formed. In addition, the way the adhesive injection and venting channels are set up also directly affects the filling quality and efficiency.

[0005] Therefore, how to achieve high-quality and high-efficiency adhesive bonding between the stator and the housing through process optimization is a technical problem that needs to be solved in this field. Summary of the Invention

[0006] The present invention aims to provide a method for connecting a motor stator and a reducer housing, thereby achieving high-quality and high-efficiency adhesive bonding between the stator and the housing.

[0007] To achieve the objectives of this invention, the technical solution adopted is as follows:

[0008] A method for connecting a motor stator and a reducer housing, wherein the motor stator is cylindrical, including a middle section and a first end and a second end with a diameter smaller than that of the middle section, and the reducer housing is a hollow barrel-shaped structure that mates with the motor stator, including a large-diameter cavity section, a small-diameter cavity section with a diameter smaller than that of the large-diameter cavity section, and a bowl-shaped connecting structure located at one end of the small-diameter cavity section, wherein the inner diameter of the small-diameter cavity section mates with the outer diameter of the second end, and includes the following steps:

[0009] S1, Embedded Positioning

[0010] Several first through holes communicating with the small-diameter cavity section are opened along the peripheral wall of the bowl-shaped connecting structure, several second blind holes are opened at the bottom of the bowl-shaped connecting structure, and the second end of the motor stator is embedded in the small-diameter cavity section of the reducer receiving device;

[0011] S2, blind hole partial coverage

[0012] After the motor stator is embedded in the small-diameter cavity, the motor stator is adjusted so that the second end part covers the second blind hole and blocks the first through hole on the peripheral wall of the bowl-shaped connecting structure, leaving only two first through holes, which serve as glue injection holes and venting holes respectively.

[0013] S3, Double-hole injection molding

[0014] Glue is injected through the injection hole to fill the gap between the bottom surface of the bowl-shaped connection structure and the second end, as well as the second blind hole;

[0015] S4, Curing

[0016] After the adhesive is applied, it cures, completing the connection.

[0017] Further, in step S1, the number of the first through holes is 4 to 12, and the hole diameter is 0.5 to 3.0 mm; the hole depth of the second blind hole is 2.0 to 10.0 mm, and the hole diameter is 1.0 to 5.0 mm, and the first through holes and the second blind holes are staggered in the circumferential position of the bowl-shaped connecting structure.

[0018] Furthermore, in step S2, when the second end portion of the motor stator covers the second blind hole, the coverage area is greater than 50% of the opening area of ​​each second blind hole; the glue injection hole is located at the lower position of the peripheral wall of the bowl-shaped connecting structure; the vent hole is located at the higher position of the peripheral wall of the bowl-shaped connecting structure, and the vent hole and the glue injection hole are arranged opposite to each other in the circumferential direction of the bowl-shaped connecting structure.

[0019] Furthermore, in step S3, the injection pressure of the adhesive when injecting the adhesive through the injection hole is 0.1 to 0.5 MPa, and the viscosity of the adhesive is 1000 to 10000 mPa·s.

[0020] Furthermore, in step S4, the adhesive is cured by heat curing at a temperature of 80–150°C for a time of 0.5–2 hours.

[0021] Furthermore, step S2 specifically includes the following steps:

[0022] S21. Confirm that the second end of the motor stator has been embedded in the small-diameter cavity of the reducer receiving device to the preset position;

[0023] S22. Insert a temporary sealing plug into the end of the motor stator away from the reducer housing to seal the internal space of the motor stator and prevent glue from overflowing.

[0024] S23. Seal the first through hole on the peripheral wall of the cup-shaped connection structure with a removable plug or tape;

[0025] S24. Select two of the first through holes from the sealed holes as injection holes and venting holes, remove the sealing material from both, and leave the remaining through holes sealed.

[0026] Furthermore, in step S3, when injecting adhesive through the injection hole, the injection parameters are switched as follows:

[0027] S31. In the initial stage, the adhesive is injected at a pressure of 0.1 to 0.2 MPa to slowly wet the mating surfaces and fill the axial gap. This stage continues until the adhesive first overflows from the vent hole.

[0028] S32. Pause the glue injection and maintain the pressure for 10-20 seconds to allow the glue to flow fully into each second blind hole under the action of gravity.

[0029] S33. Finally, apply additional glue at a pressure of 0.2 to 0.4 MPa to fill the gaps caused by glue shrinkage or filling of the second blind hole until glue overflows from the vent hole again.

[0030] Further, in step S4, the adhesive is cured as follows:

[0031] S41. The first stage is the heating stage, which raises the temperature from room temperature to curing temperature at a rate of 2-5℃ / min to avoid excessive thermal stress caused by excessive heating.

[0032] S42. The second stage is the heat preservation stage, which is maintained at the curing temperature for 0.5 to 2 hours to allow the cross-linking reaction of the adhesive to be fully completed.

[0033] S43. The third stage is the cooling stage, which involves natural cooling or programmed temperature control cooling. The cooling rate should not exceed 3℃ / min to prevent shrinkage cracks in the adhesive layer due to sudden cooling.

[0034] Furthermore, when the second end portion of the motor stator covers the second blind hole, the coverage area is 60-90% of the opening area of ​​each second blind hole.

[0035] Furthermore, the injection pressure when injecting the adhesive through the injection hole is 0.2 to 0.4 MPa, and the viscosity of the adhesive is 3000 to 8000 mPa·s.

[0036] The technical solution of the present invention has the following beneficial technical effects:

[0037] 1. This invention encapsulates the motor stator and reducer housing into one unit through four core steps: embedded positioning, partial coverage of blind holes, double-hole glue injection, and curing. The entire process does not require machining threaded holes or keyways on the stator, does not damage the structural strength of the stator, and the glue can compensate for the micro-unevenness between the mating surfaces, achieving full surface bonding.

[0038] 2. This invention covers the stator end face with a second blind hole, making each second blind hole a semi-closed glue-containing cavity—glue can smoothly enter the blind hole from the uncovered opening, while the covered part of the stator end face forms a closed end; after curing, the glue column in the blind hole is connected to the bottom glue layer through the neck, forming an anchoring structure similar to a rivet head; when subjected to axial tensile force, the pull-out of the glue column needs to overcome the interfacial shear force between the glue column and the inner wall of the blind hole, as well as the tensile force at the connection between the glue column neck and the glue layer. The pull-out resistance is much greater than that of a glue column with a completely open blind hole, thereby significantly improving the axial connection strength;

[0039] 3. The present invention adopts a dual-hole glue injection strategy. By retaining one injection hole and one vent hole, the glue enters from the injection hole under pressure and pushes the air in the cavity to be discharged towards the vent hole. Since the vent hole is unobstructed, the air in the cavity can be discharged freely without forming back pressure. This avoids the problem of back pressure forming due to compressed air, which hinders the flow of glue. The filling efficiency is high and the air bubble residue rate is low.

[0040] 4. In this invention, the glue injection hole is located at the lower position of the peripheral wall of the bowl-shaped connecting structure, and the vent hole is located at the higher position. The two are arranged opposite each other in the circumferential direction, which can maximize the circumferential flow path of the glue and ensure that the glue can be evenly distributed to each area to be filled. At the same time, the first through hole and the second blind hole are staggered in the circumferential position, that is, the center line of each first through hole is located between two adjacent second blind holes in the circumferential direction, so that the glue injected from the first through hole can be evenly distributed to each second blind hole, avoiding the glue directly impacting a certain blind hole and causing uneven filling, thus ensuring the consistency of filling of each blind hole.

[0041] 5. In this invention, the adhesive fills each space to be filled sequentially along a preset flow path during the injection process. That is, after entering through the injection hole, it first flows axially along the annular gap, then flows radially inward along the axial gap and sequentially enters each second blind hole, finally overflowing from the vent hole. This flow path design from the outside to the inside and from the axial to the radial ensures that air can be sequentially discharged from each blind hole and gap by the adhesive, and finally collected and discharged through the vent hole, effectively avoiding air bubble residue.

[0042] 6. The glue filling sequence of the present invention is automatically adjusted by the flow resistance of the internal structure of the receiving device. The glue preferentially fills the low-resistance axial gap. After the gap is filled, the injection pressure increases and the glue is then pressed into the high-resistance second and third blind holes. This adaptive filling sequence ensures that the axial gap, as the main bonding surface, is given priority to be fully filled, while the blind holes, as auxiliary anchoring structures, are filled later. This avoids the problem of the blind holes being filled first and then hindering the flow of glue to other areas.

[0043] 7. The present invention adopts a multi-stage injection method, which effectively improves the filling rate, reduces the generation of shrinkage pores, and ensures the bonding quality.

[0044] 8. Through the method of the present invention, a three-layer composite encapsulation structure of stator-adhesive layer-accommodating device is finally formed. After curing, the adhesive layer completely covers the outer peripheral surface and end face of the second end of the stator and firmly bonds to the inner peripheral surface and bottom wall of the small-diameter cavity section of the accommodation device. The adhesive layer also fills the second blind hole on the bottom wall and the first through hole on the peripheral wall, forming multi-point anchoring. This encapsulation method integrates the stator and the accommodation device into a non-removable integral component. The adhesive layer is both an adhesive and a structural filling material, and simultaneously undertakes the triple functions of connection, sealing and vibration reduction.

[0045] 9. After curing, the spatial distribution of the adhesive on the connection interface forms a three-dimensional network from the axial adhesive surface to the blind hole adhesive pillar, to the annular adhesive strip, to the radial adhesive pin, which fully locks the stator and the housing device in the axial, radial and circumferential dimensions. The final connection structure has high connection strength in the axial, radial and circumferential dimensions, which can meet the stringent use requirements of robot joints under frequent start-stop and forward and reverse rotation conditions. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the connection process of the present invention;

[0047] Figure 2 This is a schematic diagram of the overall structure after connection according to an embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of the motor stator structure in an embodiment of the present invention;

[0049] Figure 4 This is a schematic diagram of the reducer housing device in an embodiment of the present invention;

[0050] Figure 5 This is a schematic diagram of the structure at the small-diameter cavity segment in an embodiment of the present invention;

[0051] Figure 6 This is a schematic diagram of the structure inside the large-diameter cavity section in an embodiment of the present invention.

[0052] The following are labels in the attached diagram: motor stator 1, middle section 11, first end 12, second end 13, reducer housing 2, large diameter cavity section 21, small diameter cavity section 22, first through hole 3, second blind hole 4, third blind hole 5. Detailed Implementation

[0053] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0054] Example 1:

[0055] This embodiment provides a method for connecting the motor stator and the reducer housing device, such as... Figure 2 ,3 As shown in Figure 4, the motor stator 1 is cylindrical, having a middle section 11 and a first end section 12 and a second end section 13 located at both ends. The diameter of the middle section 11 is larger than the diameter of the two end sections. The reducer housing 2 has a hollow cavity extending axially, including a large-diameter cavity section 21 and a small-diameter cavity section 22. The inner diameter of the large-diameter cavity section 21 is larger than the inner diameter of the small-diameter cavity section 22. The inner diameter of the large-diameter cavity section 21 matches the diameter of the middle section 11 of the motor stator 1, allowing the middle section 11 to be accommodated within the large-diameter cavity section 21; the inner diameter of the small-diameter cavity section 22 matches the diameter of the second end section 13, allowing the second end section 13 to be embedded within the small-diameter cavity section 22. Figure 5 As shown, a bowl-shaped connecting structure is provided at one end of the small-diameter cavity section 22. This size-matching design ensures that the motor stator 1 and the reducer housing 2 have a defined radial positional relationship after assembly, providing a uniform annular gap for subsequent glue filling.

[0056] like Figure 1 As shown, the connection method includes the following steps:

[0057] S1, Embedded Positioning

[0058] A number of first through holes 3 connected to the small diameter cavity section 22 are opened along the peripheral wall of the bowl-shaped connecting structure, a number of second blind holes 4 are opened at the bottom of the bowl-shaped connecting structure, and the second end 13 of the motor stator 1 is embedded in the small diameter cavity section 22 of the reducer receiving device 2.

[0059] The second blind hole 4 is evenly or non-uniformly distributed along the circumference and does not penetrate the bottom surface. The diameter of the second blind hole 4 is in the range of 1.0 mm to 5.0 mm, and the depth is in the range of 2.0 mm to 10.0 mm. A plurality of first through holes 3 are formed on the peripheral wall. These first through holes 3 penetrate the thickness of the peripheral wall, and the diameter is in the range of 0.5 mm to 3.0 mm. The number of these holes is 4 to 12, and they are evenly distributed along the circumference.

[0060] The first through holes 3 on the peripheral wall of the bowl-shaped connecting structure and the second blind holes 4 on the bottom surface are staggered in the circumferential direction, that is, the center line of each first through hole 3 is located between two adjacent second blind holes 4 in the circumferential direction. This staggered arrangement allows the glue injected from the first through holes 3 to be evenly distributed to each of the second blind holes 4, avoiding the glue directly impacting a blind hole and causing uneven filling.

[0061] S2, blind hole partial coverage

[0062] After the motor stator 1 is embedded in the small-diameter cavity section 22, the motor stator 1 is adjusted so that the second end 13 partially covers the second blind hole 4 and blocks the first through hole 3 on the peripheral wall of the bowl-shaped connecting structure, leaving only two first through holes 3, which serve as glue injection holes and venting holes respectively.

[0063] The injection port is located at the lower part of the peripheral wall of the bowl-shaped connection structure, while the vent is located at the higher part. They are positioned circumferentially opposite each other, i.e., distributed at 180°, to maximize the circumferential flow path of the adhesive. During injection, the adhesive enters through the injection port under pressure, pushing the air inside the cavity towards the vent. Because the vent is unobstructed, the air inside the cavity can be freely discharged, avoiding the problem of back pressure caused by compressed air hindering adhesive flow. Compared to single-hole injection, this dual-hole strategy improves filling efficiency by more than 50% and reduces the air bubble residue rate to below 2%.

[0064] S3, Double-hole injection molding

[0065] Glue is injected through the injection hole to fill the gap between the bottom surface of the bowl-shaped connection structure and the second end 13, as well as the second blind hole 4.

[0066] The order in which the adhesive is applied is automatically adjusted by the flow resistance of the internal structure of the reducer receiving device 2. For example... Figure 5 , 6 As shown, the bowl-shaped connecting structure is an annular boss with an outer ring featuring alternating concave and convex toothed structures. The circumferential surface of the bowl-shaped connecting structure also has a third blind hole 5 evenly distributed inwards. Simultaneously, several stepped annular bosses are sequentially arranged on the inner side of the large-diameter cavity section 21 of the reducer housing 2, facing the small-diameter cavity section 22. The second blind hole 4 has a relatively high flow resistance due to its smaller diameter and greater depth; while the axial gap has a larger flow cross-section and lower flow resistance. Therefore, the adhesive preferentially fills the low-resistance axial gap. After the gap is filled, the injection pressure increases, and the adhesive is then forced into the high-resistance second blind hole 4 and third blind hole 5. This adaptive filling sequence ensures that the axial gap, as the primary bonding surface, is preferentially and fully filled, while the blind holes, as auxiliary anchoring structures, are filled later, avoiding the problem of the blind holes being preferentially filled and hindering the flow of adhesive to other areas.

[0067] S4, Curing

[0068] After the adhesive is applied, it cures, completing the connection.

[0069] The connection method provided in this embodiment encapsulates the motor stator 1 and the reducer housing 2 into a single unit through four core steps: embedding and positioning, partial coverage of blind holes, dual-hole glue injection, and curing. The embedding step utilizes the inherent geometry of the motor stator 1 and the reducer housing 2 to achieve initial axial and radial positioning, eliminating the need for additional positioning fixtures. The partial coverage of blind holes creates a semi-closed glue-receiving cavity for each second blind hole 4—glue can smoothly enter the blind hole from the uncovered opening, while the covered portion of the stator end face forms a closed end. After curing, the glue column within the blind hole is connected to the bottom glue layer via the neck, forming an anchoring structure similar to a rivet head. The dual-hole glue injection strategy, by retaining one injection hole and one vent hole, allows glue to enter through the injection hole under pressure and pushes the air in the cavity towards the vent hole. Air can escape freely without creating back pressure, resulting in high filling efficiency and low air bubble residue. The curing step transforms the glue from a liquid to a solid state, firmly bonding the motor stator 1 and the reducer housing 2. This method requires no machining of threaded holes or keyways on the stator, does not compromise the structural strength of the stator, and the adhesive can compensate for the microscopic unevenness between the mating surfaces, achieving full-surface bonding. The resulting connection structure has high connection strength in the axial, radial, and circumferential dimensions, with an axial tensile strength of not less than 20 MPa and a circumferential torsional strength of not less than 15 MPa, which can meet the stringent requirements of robot joints under frequent start-stop and forward / reverse rotation conditions.

[0070] Simultaneously, during the injection process, the adhesive sequentially fills each space to be filled along a preset flow path. After entering through the injection hole, the adhesive first flows axially along the annular gap between the outer circumferential surface of the second end 13 of the stator and the inner circumferential surface of the small-diameter cavity section 22, reaching the bottom area of ​​the bowl-shaped connection structure. Subsequently, the adhesive flows radially inward along the axial gap between the bottom surface and the stator end face, sequentially entering each of the second blind holes 4 during the flow process. At the same time, the adhesive also diffuses circumferentially, entering the third blind hole 5 and the groove on the annular boss. Finally, the adhesive overflows from the vent hole, indicating that the filling is complete. This flow path design from the outside to the inside and from the axial to the radial ensures that air can be sequentially discharged from each blind hole and gap by the adhesive, and finally collected and discharged through the vent hole, avoiding air bubble residue.

[0071] The connection method provided in this embodiment ultimately forms a three-layer composite encapsulation structure consisting of a motor stator, an adhesive layer, and a reducer housing. After curing, the adhesive layer completely covers the outer peripheral and end faces of the second end 13 and firmly bonds it to the inner peripheral surface and bottom wall of the small-diameter cavity section 22. The adhesive layer also fills the second blind hole 4 on the bottom wall, the first through hole 3 on the peripheral wall, the third blind hole 5 on the annular boss, and the groove, forming multi-point anchoring. This encapsulation method integrates the stator and housing into a single, non-removable component. The adhesive layer serves as both an adhesive and a structural filler, simultaneously fulfilling the triple functions of connection, sealing, and vibration damping.

[0072] Example 2:

[0073] In Example 1, the area ratio of the second end 13 of the motor stator 1 covering the opening of the second blind hole 4 is a key parameter affecting the connection strength. In this example, the coverage area ratio is between 50% and 95%. As the ratio increases, the anchoring effect of the adhesive column inside the second blind hole 4 is enhanced, but the difficulty of the adhesive entering the blind hole also increases. When the ratio is between 60% and 90%, the connection strength reaches the optimal range—ensuring that the adhesive can smoothly enter the second blind hole 4 while also providing sufficient closed anchoring effect for the adhesive column. When the ratio exceeds 95%, the path for the adhesive to enter the second blind hole 4 is too narrow, and the filling rate decreases significantly; when the ratio is below 50%, the second blind hole 4 is too open, and the anchoring effect of the adhesive column is weakened. This optimal ratio range, determined through finite element analysis and pull-out tests, can increase the axial tensile strength by more than 50% compared to the completely open scheme.

[0074] Example 3:

[0075] In this embodiment, the injection pressure is set within the range of 0.1 MPa to 0.5 MPa. The driving force generated by this pressure range is sufficient to overcome the flow resistance of the adhesive in a gap of 0.05 mm to 0.5 mm, while preventing adhesive splashing, stator displacement, or deformation of the receiving device due to excessive pressure. During the flow of the adhesive, the pressure gradually decreases along the flow path, and drops to atmospheric pressure when it reaches the vent, ensuring that the adhesive will not spray out from the vent.

[0076] The injection pressure and filling time are inversely proportional. At an injection pressure of 0.1 MPa and a glue viscosity of 5000 mPa·s, the filling time is approximately 60 to 120 seconds; at 0.3 MPa, the filling time is reduced to 20 to 40 seconds; and at 0.5 MPa, the filling time is further reduced to 10 to 20 seconds. The preferred injection pressure range is 0.2 MPa to 0.4 MPa, within which shorter filling times and lower defect rates can be obtained.

[0077] Example 4:

[0078] In this embodiment, the viscosity of the adhesive is between 1000 mPa·s and 10000 mPa·s, preferably between 3000 mPa·s and 8000 mPa·s. When the viscosity is below 1000 mPa·s, the adhesive is too fluid and easily leaks through the gaps between the parts, and the cured adhesive layer has a large shrinkage rate. When the viscosity is above 10000 mPa·s, the flow resistance of the adhesive in narrow gaps is too high, the filling time is too long, and it is difficult to enter small blind holes. The selected adhesive has a suitable viscosity at the injection temperature, ensuring that filling is completed within a reasonable time while having good gap retention ability and low curing shrinkage rate.

[0079] Example 5:

[0080] In this embodiment, the adhesive is cured using a thermosetting process. The curing temperature is between 80°C and 150°C, and the curing time is between 30 minutes and 2 hours. Curing temperature and time are inversely proportional; the higher the temperature, the shorter the required curing time. However, excessively high curing temperatures may cause aging of the stator winding insulation material or thermal deformation of the housing; excessively low curing temperatures result in incomplete curing and insufficient adhesive layer strength. Preferably, the curing temperature is between 100°C and 120°C, and the curing time is between 45 and 60 minutes. Under these conditions, the adhesive curing degree can reach over 95%, and the mechanical properties of the adhesive layer meet the design values.

[0081] Example 6:

[0082] In this embodiment, specialized dispensing fixtures and equipment are used for adhesive injection, including a precision dispensing pump, pressure sensor, flow meter, and control system. The dispensing accuracy of the dispensing pump is no less than ±1% of the set value. It also includes a clamp for fixing the motor stator 1 and the reducer housing 2, a plug for sealing the first through hole 3, and a temporary sealing plug for insertion from one end of the stator. The clamp is designed with an upward-facing vent hole to ensure that the vent hole is located at the highest point of the assembly during dispensing. The plug is made of elastic material, which can tightly seal the first through hole and is easy to remove after dispensing. The temporary sealing plug is made of heat-resistant material, which can maintain its shape and sealing performance at the curing temperature.

[0083] Before applying the adhesive, the following preparations are required: First, confirm that the second end 13 has been embedded in the small-diameter cavity 22 to the preset position; second, insert a temporary sealing plug into the end of the motor stator 1 away from the reducer housing 2 to seal the internal space of the stator and prevent adhesive from overflowing; third, seal the first through hole 3 on the peripheral wall of the cup-shaped connecting structure using a removable plug or tape; fourth, select two of the sealed first through holes 3 as the adhesive injection hole and the vent hole, remove the sealing materials from both, and leave the remaining through holes sealed. This sequence ensures that all unexpected openings are reliably sealed before adhesive application, preventing adhesive leakage during the application process.

[0084] Pre-treat the adhesive before application. Mix the two-component adhesive according to the manufacturer's recommended ratio. Mixing can be done using a static mixing tube or dynamic stirring, with a mixing time of at least 2 minutes to ensure thorough and uniform mixing of the two components. After mixing, perform vacuum degassing treatment. The degassing vacuum degree should not be lower than -0.095 MPa, and the degassing time should be 5 to 10 minutes to remove air bubbles introduced during mixing. The degassed adhesive should be used within its shelf life, which is typically 30 to 60 minutes. If the ambient temperature is high, the shelf life will be shortened accordingly, and the amount of adhesive mixed per batch should be adjusted based on the actual situation.

[0085] The glue injection operation is performed according to the following steps: Step 1, fix the assembled motor stator 1 and reducer housing 2 assembly onto the glue injection fixture, ensuring the glue injection hole is in the low position and the vent hole is in the high position. Step 2, connect the glue injection pump to the glue injection hole, ensuring a reliable seal at the interface. Step 3, start the glue injection pump and begin injection at the preset low pressure. Step 4, observe the vent hole; stop injection after glue overflows from the vent hole. Step 5, hold the pressure for 10 to 20 seconds, then inject more glue at a higher pressure until glue overflows from the vent hole again. Step 6, turn off the glue injection pump, disconnect the glue injection pipeline, and quickly seal the glue injection hole with a plug, leaving the vent hole open to balance the air pressure changes during the curing process. Step 7, transfer the glue-injected assembly to the curing area.

[0086] The glue injection parameters are switched according to the following sequence: In the initial stage, glue is injected at a lower pressure to slowly wet the mating surfaces and fill the axial gaps. This stage continues until the glue first overflows from the vent hole. Then, glue injection is paused, and pressure is maintained for 10 to 20 seconds to allow the glue to fully flow into each blind hole and groove under gravity. Finally, glue is injected again at a higher pressure to fill the gaps caused by glue shrinkage or blind hole filling, until glue overflows from the vent hole again. This multi-stage glue injection strategy effectively improves the filling rate and reduces the generation of shrinkage voids.

[0087] An anomaly detection and interruption mechanism is implemented during the glue injection process. A sudden drop in injection pressure indicates a leak; or a continuous rise in pressure without a decrease indicates a blockage in the venting channel. In this case, glue injection will automatically stop and an alarm will sound. Operators will check the sealing status and ensure the venting holes are clear. After troubleshooting, glue injection can resume. If the interruption exceeds the glue's shelf life, the component must be disassembled, cleaned, and re-inserted with new glue.

[0088] Key parameters are monitored and recorded in real time during the dispensing process. Monitored parameters include dispensing pressure, dispensing flow rate, dispensing volume, ambient temperature, and humidity. These parameters are transmitted to the control system in analog or digital signal form, with a sampling frequency of no less than 10Hz to ensure real-time monitoring and post-dispensing traceability. The dispensing pressure sampling frequency is 50Hz to 100Hz, with a quantization accuracy of no less than 12 bits. The pressure signal undergoes digital filtering to remove high-frequency noise and electromagnetic interference; the filtered pressure value is used for real-time control and anomaly detection during the dispensing process. When the filtered pressure value exceeds a preset threshold range, the system triggers an alarm or automatically shuts down. The pressure data is stored for the complete dispensing cycle of each batch of products, facilitating subsequent quality analysis and process optimization. The dispensing process parameters for each batch of products are stored in a process parameter database. Each record in the database is associated with a unique identifier for that batch of products. When quality problems occur in subsequent products, the complete dispensing process data for that batch can be traced through the identifier, allowing for analysis of the cause of the problem and optimization of process parameters.

[0089] After the adhesive is applied, defoaming is performed using a vacuum defoaming method.

[0090] Example 7:

[0091] Based on Embodiment 6, this embodiment also provides the assembly of the motor stator 1 and the reducer receiving device 2 before glue injection, which is carried out according to the following steps: First, the outer surface of the second end 13 and the inner surface of the small-diameter cavity section 22 are cleaned to remove oil, rust, and particles. The cleaning method can be ultrasonic cleaning or solvent wiping. Then, the mating surfaces are dried to ensure that there is no residual cleaning agent. Next, the reducer receiving device 2 is fixed on the assembly fixture with the opening of the small-diameter cavity section 22 facing upward; the motor stator 1 is clamped with the second end 13 facing downward and slowly inserted into the reducer receiving device 2 axially. During the insertion process, the inner wall of the small-diameter cavity section 22 guides the stator end, and the insertion speed is controlled between 1 mm / s and 5 mm / s. After insertion, the assembly is confirmed to be in place by detecting the contact state between the end face of the motor stator 1 and the bottom surface of the bowl-shaped connecting structure or by measuring the embedding depth.

[0092] Example 8:

[0093] In this embodiment, the adhesive curing process follows a specific temperature-time curve. The first stage is the heating stage, where the temperature is increased from room temperature to the curing temperature at a rate of 2°C / min to 5°C / min. The heating rate is chosen to account for the differences in the thermal expansion coefficients of the components, avoiding excessive thermal stress caused by rapid heating. The second stage is the heat preservation stage, where the temperature is maintained at the curing temperature for 30 minutes to 2 hours to ensure the cross-linking reaction of the adhesive is fully completed. The third stage is the cooling stage, where natural cooling or programmed temperature-controlled cooling is used, with a cooling rate not exceeding 3°C / min to prevent shrinkage cracks in the adhesive layer due to sudden cooling. Throughout the curing process, the component maintains a fixed posture to avoid vibration and displacement, ensuring the geometric accuracy of the cured adhesive layer.

[0094] During the curing process, the adhesive undergoes a phase transition from liquid to gel and then to solid. In the liquid stage, the adhesive is fluid, filling gaps and expelling air bubbles. In the gel stage, the adhesive loses its fluidity but has not yet reached its final strength; at this stage, external forces or displacement should be avoided on the component. In the solid stage, the adhesive reaches its designed strength, and the component can be further processed or assembled. By controlling the curing temperature and time, the timing of the phase transition process can be precisely controlled, ensuring a sufficient potting window and achieving the required performance after curing.

[0095] After curing, the following post-processing steps are performed: First, remove the vent plugs and temporary seals, checking that the plugs were removed intact and that the internal channels of the stator were unobstructed. Second, clean up any excess adhesive. If excess adhesive is present, wipe it off with solvent before it is fully cured, or remove it by machining after curing. Next, conduct a visual and dimensional inspection of the connection structure to confirm that the adhesive layer is free of obvious bubbles, cracks, and missing adhesive, and that the module's dimensions meet design requirements. Finally, perform non-destructive testing or sampling destructive testing on the connection structure. Only after confirming that the connection quality is qualified can the module proceed to the next process.

[0096] After curing, the adhesive's spatial distribution at the interface between the motor stator 1 and the reducer housing 2 exhibits the following characteristics: Between the second end 13 and the bottom surface of the bowl-shaped connecting structure, the adhesive forms a continuous annular adhesive surface with a thickness between 0.05mm and 0.5mm, covering the entire end-face contact area; within each of the second blind holes 4, the adhesive forms columnar adhesive columns, whose shape is consistent with the inner cavity of the blind hole, with an axial length equal to the depth of the blind hole and a radial dimension equal to the inner diameter of the blind hole; within the third blind hole 5 and the groove of the annular boss, the adhesive forms dotted adhesive columns and arc-shaped adhesive strips, respectively, alternately arranged on the circumferential sidewall of the annular boss; within the first through hole 3 of the circumferential wall, the adhesive forms radially penetrating adhesive pins. These adhesive bonding units spatially constitute a three-dimensional network from the axial adhesive surface to the blind hole adhesive columns, to the annular adhesive strips, and to the radial adhesive pins, comprehensively locking the stator and housing device in the axial, radial, and circumferential dimensions.

[0097] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any modifications or equivalent changes made based on the technical essence of the present invention shall still fall within the scope of protection claimed by the present invention.

Claims

1. A method for connecting a motor stator and a reducer housing, wherein the motor stator is cylindrical, comprising a middle section and a first end and a second end with a diameter smaller than that of the middle section, and the reducer housing is a hollow barrel-shaped structure that mates with the motor stator, comprising a large-diameter cavity section, a small-diameter cavity section with a diameter smaller than that of the large-diameter cavity section, and a bowl-shaped connecting structure located at one end of the small-diameter cavity section, wherein the inner diameter of the small-diameter cavity section mates with the outer diameter of the second end, characterized in that, Includes the following steps: S1, Embedded Positioning: Several first through holes communicating with the small-diameter cavity section are opened along the peripheral wall of the bowl-shaped connecting structure, several second blind holes are opened at the bottom of the bowl-shaped connecting structure, and the second end of the motor stator is embedded in the small-diameter cavity section of the reducer receiving device; S2, partial coverage of blind holes: After the motor stator is embedded in the small-diameter cavity, the motor stator is adjusted so that the second end part covers the second blind hole and blocks the first through hole on the peripheral wall of the bowl-shaped connecting structure, leaving only two first through holes, which serve as glue injection holes and venting holes respectively. S3, Dual-hole injection: Glue is injected through the injection hole to fill the gap between the bottom surface of the bowl-shaped connection structure and the second end, as well as the second blind hole; S4, Curing: After the adhesive is applied, it cures, completing the connection.

2. The method for connecting the motor stator and the reducer housing according to claim 1, characterized in that, In step S1, the number of the first through holes is 4 to 12, and the hole diameter is 0.5 to 3.0 mm; the hole depth of the second blind hole is 2.0 to 10.0 mm, and the hole diameter is 1.0 to 5.0 mm, and the first through holes and the second blind holes are staggered in the circumferential position of the bowl-shaped connecting structure.

3. The method for connecting the motor stator and the reducer housing according to claim 2, characterized in that, In step S2, when the second end portion of the motor stator covers the second blind hole, the coverage area is greater than 50% of the opening area of ​​each second blind hole; the glue injection hole is located at the lower position of the peripheral wall of the bowl-shaped connecting structure; the vent hole is located at the higher position of the peripheral wall of the bowl-shaped connecting structure, and the vent hole and the glue injection hole are arranged opposite to each other in the circumferential direction of the bowl-shaped connecting structure.

4. The method for connecting the motor stator and the reducer housing according to claim 3, characterized in that, In step S3, the injection pressure of the glue through the injection hole is 0.1 to 0.5 MPa, and the viscosity of the glue is 1000 to 10000 mPa·s.

5. The method for connecting the motor stator and the reducer housing according to claim 4, characterized in that, In step S4, the adhesive is cured by heat curing at a temperature of 80–150°C for 0.5–2 hours.

6. The method for connecting the motor stator and the reducer housing according to claim 5, characterized in that, Step S2 specifically includes the following steps: S21. Confirm that the second end of the motor stator has been embedded in the small-diameter cavity of the reducer receiving device to the preset position; S22. Insert a temporary sealing plug into the end of the motor stator away from the reducer housing to seal the internal space of the motor stator and prevent glue from overflowing. S23. Seal the first through hole on the peripheral wall of the cup-shaped connection structure with a removable plug or tape; S24. Select two of the first through holes from the sealed holes as injection holes and venting holes, remove the sealing material from both, and leave the remaining through holes sealed.

7. The method for connecting the motor stator and the reducer housing according to claim 6, characterized in that, In step S3, when injecting glue through the injection hole, switch the injection parameters as follows: S31. In the initial stage, the adhesive is injected at a pressure of 0.1 to 0.2 MPa to slowly wet the mating surfaces and fill the axial gap. This stage continues until the adhesive first overflows from the vent hole. S32. Pause the glue injection and maintain the pressure for 10-20 seconds to allow the glue to flow fully into each second blind hole under the action of gravity. S33. Finally, apply additional glue at a pressure of 0.2 to 0.4 MPa to fill the gaps caused by glue shrinkage or filling of the second blind hole until glue overflows from the vent hole again.

8. The method for connecting the motor stator and the reducer housing according to claim 7, characterized in that, In step S4, the adhesive is cured as follows: S41. The first stage is the heating stage, which raises the temperature from room temperature to curing temperature at a rate of 2-5℃ / min to avoid excessive thermal stress caused by excessive heating. S42. The second stage is the heat preservation stage, which is maintained at the curing temperature for 0.5 to 2 hours to allow the cross-linking reaction of the adhesive to be fully completed. S43. The third stage is the cooling stage, which involves natural cooling or programmed temperature control cooling. The cooling rate should not exceed 3℃ / min to prevent shrinkage cracks in the adhesive layer due to sudden cooling.

9. A method for connecting a motor stator and a reducer housing according to claim 3, characterized in that, When the second end portion of the motor stator covers the second blind hole, the coverage area is 60-90% of the opening area of ​​each second blind hole.

10. A method for connecting a motor stator and a reducer housing according to claim 4, characterized in that, The injection pressure when injecting the adhesive through the injection hole is 0.2 to 0.4 MPa, and the viscosity of the adhesive is 3000 to 8000 mPa·s.

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