Cycloid speed reducer and motor integrated temperature control system

Abstract

The invention relates to a cycloid speed reducer and motor integrated temperature control system which is characterized in that an inner flange is arranged in the middle in a heat dissipation shell, the part, close to the inner wall of the heat dissipation shell, of the inner flange forms a motor mounting table, and a motor is fixed to the rear side of the motor mounting table; the speed reducer is fixedly connected with the front end of the heat dissipation shell through a flange on a shell of the speed reducer. A front group of cooling flow channels and a rear group of cooling flow channels are arranged in the heat dissipation shell and correspond to the speed reducer and the motor respectively; the close ends of the two groups of cooling runners are inlet ends which are respectively connected with two water outlets of the shunting three-way valve; water inlets of the shunt three-way valves are connected with the cooling pump through pipelines; wireless temperature measuring sensors are embedded and fixed in temperature measuring sensor mounting grooves, corresponding to tooth roots, on the outer sides of two cycloidal gears of the speed reducer; a three-axis MEMS vibration sensor is embedded and fixed in a vibration sensor mounting groove in the inner side wall, close to the cycloidal gear, of a planet carrier of the speed reducer; the FPGA control unit is installed in the motor end cover in an embedded mode, and dynamic adjustment of the opening degree of the three-way valve and the power of the cooling pump is achieved.

Description

Technical Field

[0001] This invention belongs to the field of geared motor technology, and particularly relates to a temperature control system integrating a cycloidal reducer and a motor. Background Technology

[0002] With the popularization of intelligent manufacturing and new energy equipment, geared motor systems are developing towards higher power density and compactness. Application scenarios such as industrial robots and electric vehicle drive systems require equipment to carry higher loads in a smaller space, but existing reducers and motors mostly adopt independent heat dissipation designs, which have problems such as low heat dissipation efficiency, large space occupation, and high energy consumption.

[0003] Overheating failures in speed reducers are mostly caused by overload operation, worn oil seals, or poor lubrication, while temperature rise problems in motors due to blocked cooling fans or poor ventilation occur frequently in industrial settings. In particular, the heat dissipation capacity of natural cooling systems drops sharply in high-temperature, high-dust environments, leading to a shortened equipment lifespan. Furthermore, separate heat dissipation designs complicate heat conduction paths, making it difficult for the independent heat dissipation structures of the reducer housing and motor casing to achieve coordinated heat management, resulting in frequent localized overheating. Therefore, an efficient heat dissipation system is a key factor in ensuring stable equipment operation. Current market solutions suffer from structural redundancy, low heat dissipation efficiency, and high maintenance costs, necessitating a highly efficient, compact, and intelligent heat dissipation solution. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes an integrated temperature control system for a cycloidal reducer and a motor.

[0005] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0006] A temperature control system integrating a cycloidal reducer and a motor includes a cycloidal reducer, a heat sink housing, a cooling channel, a wireless temperature sensor, a flow divider three-way valve, a motor, an FPGA control unit, and a triaxial MEMS vibration sensor.

[0007] The heat sink housing is made of high-strength aluminum alloy and is cylindrical in shape. An inner flange is provided in the middle of the heat sink housing. The part of the inner flange near the inner wall of the heat sink housing forms a motor mounting platform. The motor is fixed to the rear side of the motor mounting platform inside the heat sink housing. The cycloidal reducer is fixedly connected to the front end of the heat sink housing through a flange on its outer shell, so that the cycloidal reducer extends into the front part of the heat sink housing.

[0008] The heat dissipation housing has two sets of cooling channels built in, one in front and one in back. The front set of cooling channels corresponds to the cycloidal reducer, and the rear set of cooling channels corresponds to the motor. The end closest to the two sets of cooling channels is the inlet end, and the inlet ends of the two sets of cooling channels are respectively connected to the two outlets of the diversion three-way valve. The inlet of the diversion three-way valve is connected to the external cooling pump through a pipeline.

[0009] Temperature sensor mounting slots are provided on the outer sides of the two cycloidal wheels of the cycloidal reducer at the locations corresponding to the tooth roots. Wireless temperature sensors are embedded and fixed in the sensor mounting slots on both sides.

[0010] A vibration sensor mounting slot is provided on the inner side wall of the planetary carrier of the cycloidal reducer near the cycloidal wheel, and a triaxial MEMS vibration sensor is embedded and fixed in the vibration sensor mounting slot.

[0011] The FPGA control unit is embedded inside the motor end cover. Based on the detection values ​​of the wireless temperature sensor and the triaxial MEMS vibration sensor, it runs a vibration-temperature dual closed-loop algorithm to dynamically adjust the opening of the three-way valve and the power of the cooling pump.

[0012] Furthermore, the inner flange has an annular groove on the front and rear surfaces near the center of the heat dissipation housing; the annular grooves on both sides are filled with a phase change material layer, which is a graphene-reinforced phase change material, and a micro heat pipe array is pre-embedded in the phase change material layer.

[0013] Moreover, the two sets of cooling channels adopt a variable diameter spiral channel design, with the inlet section of the spiral channel being a narrow diameter section and the outlet section being an expanding diameter section; a nano-ceramic coating is sprayed on the inner wall of the cooling channel.

[0014] Furthermore, the diverter valve precisely adjusts the coolant distribution ratio according to the instructions of the FPGA control unit: the initial preset state is 70:30, with priority given to motor cooling; when the ambient temperature is >40℃ or the motor load is >80% of the rated power, the diverter valve automatically switches to a 50:50 balanced mode, evenly distributing coolant to the cooling channels corresponding to the motor and the cycloidal reducer; when the reducer input torque is >120% of the rated torque, the distribution ratio is adjusted to 40:60, achieving priority cooling for the cycloidal reducer; and a high-precision pressure sensor is integrated into the diverter valve.

[0015] Furthermore, the FPGA control unit has a built-in Q-learning reinforcement learning model, which uses temperature uniformity, energy consumption coefficient, and vibration RMS value as reward functions to optimize control parameters through online learning. The control parameters include PID parameters and three-way valve opening curve parameters.

[0016] Moreover, the temperature loop in the vibration-temperature dual closed-loop algorithm adopts an incremental PID control algorithm. The control target is that the temperature difference between the key parts of the motor and the reducer is ≤5℃. The temperature is collected in real time by the wireless temperature sensor, and the PWM signal is output after PID calculation to control the displacement of the three-way valve core.

[0017] Moreover, the vibration loop in the vibration-temperature dual closed-loop algorithm adopts an adaptive filtering algorithm based on order analysis: firstly, the signal collected by the triaxial MEMS vibration sensor is subjected to order tracking to extract the vibration energy of the meshing frequency and its harmonic components; when the vibration energy of a certain order exceeds the threshold, the system automatically adjusts the cooling pump power to suppress the transmission of vibration energy by changing the coolant flow rate.

[0018] Furthermore, an oil slinger is integrally formed on the main shaft that connects the motor output end and the cycloidal reducer input end.

[0019] The advantages and positive effects of this invention are as follows:

[0020] 1. This invention mounts the motor and cycloidal reducer in the same heat dissipation housing. Two sets of heat dissipation channels are built into the heat dissipation housing and connected to the same three-way valve. The three-way valve adjusts the cooling water diversion ratio according to the heat generation of the motor and cycloidal reducer, achieving efficient heat conduction and uniform distribution. This reduces the temperature rise of key components. Compared with the existing independent heat dissipation of the motor and reducer, this invention improves heat exchange efficiency and solves the thermal coupling problem.

[0021] 2. This invention introduces temperature-vibration coordinated regulation, which uses sensors to monitor the temperature and vibration signals of key parts in real time and dynamically adjusts the heat dissipation mode to adapt to dynamic working conditions.

[0022] 3. This invention integrates the cooling channel into the heat dissipation housing outside the reducer and motor. Compared with the existing heat dissipation system, which occupies additional space, it achieves zero space occupation and optimizes space utilization. It is suitable for compact scenarios such as robot joints and electric vehicle drive systems. Attached Figure Description

[0023] Figure 1 This is an overall sectional view of the present invention;

[0024] Figure 2 yes Figure 1 Enlarged view of section A in the image;

[0025] Figure 3 yes Figure 1 Enlarged view of section B in the image;

[0026] Figure 4 This is a schematic diagram of the appearance of the present invention;

[0027] Figure 5This is a schematic diagram of the heat dissipation channels on the outer casing of the present invention;

[0028] In the diagram: 1. Heat sink housing; 1.1. Cooling channel; 1.2. Inner flange; 1.3. Heat dissipation fin; 2. Diverter three-way valve; 3. Cycloidal reducer; 3.1. Cycloidal wheel; 3.2. Planetary carrier; 4. Wireless temperature sensor; 5. Triaxial MEMS vibration sensor; 6. Oil slinger impeller; 7. Miniature heat pipe array; 8. Phase change material layer; 9. Motor; 10. FPGA control unit. Detailed Implementation

[0029] 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.

[0030] Please refer to the integrated temperature control system for a cycloidal reducer and motor. Figures 1-5 The invention comprises: a cycloidal reducer 3, a heat sink housing 1, a cooling channel 1.1, a wireless temperature sensor 4, a flow divider three-way valve 2, a phase change material layer 8, a micro heat pipe array 7, an oil slinger impeller 6, a motor 9, an FPGA control unit 10, and a triaxial MEMS vibration sensor 5. The wireless temperature sensor can be a fiber Bragg grating sensor. The triaxial MEMS vibration sensor is a wireless sensor.

[0031] The heat sink housing is made of high-strength aluminum alloy and formed using an integrated casting process. The housing is cylindrical, with an inner flange 1.2 located in the center. The portion of this inner flange near the inner wall of the housing forms a motor mounting platform. Screw holes are provided around the circumference of this platform, allowing the motor to be fixed to the rear of the inner flange within the housing using screws. Annular grooves are located on the front and rear surfaces of the inner flange near the center of the housing. A phase change material layer, which can be graphene-reinforced, is filled within these grooves to absorb transient thermal shocks during motor start-up and shutdown, reducing temperature fluctuations at the cycloidal gear tooth root. The micro heat pipe array is pre-embedded within the phase change material layer. During installation, the solid phase change material is heated to a molten state and filled around the heat pipes via injection or casting. After cooling and solidification, a tight bond is formed. Grooves or fins can be machined onto the surface of the micro heat pipes to increase the contact area with the phase change material, accelerating heat transfer from the phase change layer to the cooling channels and preventing heat buildup.

[0032] The cycloidal reducer is fixedly connected to the front end of the heat sink housing via a flange on its outer shell, so that the cycloidal reducer extends into the front part of the heat sink housing.

[0033] The heat dissipation housing has two sets of cooling channels built in, one front and one rear. The front cooling channel corresponds to the cycloidal reducer, and the rear cooling channel corresponds to the motor. The two sets of cooling channels can be spiral channels arranged symmetrically, or they can be circumferential or axial channels. Spiral flow is preferred in this invention. The near ends of the two sets of cooling channels are the inlet ends, which are respectively connected to the two outlets of a diverter valve to achieve diverted input of the cooling medium. The inlet of the diverter valve is connected to an external cooling pump via a pipeline, and the cooling pump is used to draw in the cooling medium.

[0034] The cooling channel cross-section employs a variable diameter design. Specifically, the inlet section features a reduced diameter (20% smaller than the middle section) to accelerate fluid turbulence using the Venturi effect; the middle section maintains a stable flow velocity for balanced heat dissipation; and the outlet section expands its diameter by 30% (compared to the middle section), reducing pumping energy consumption through pressure relief. The inner wall of the cooling channel is coated with a nano-ceramic coating, which significantly reduces fluid flow resistance, while its smooth surface inhibits the adhesion and scaling of impurities in the coolant, extending the channel's service life. Water or oil can be used as the coolant depending on the operating conditions.

[0035] In addition, grooves are evenly distributed on the surface of the heat sink housing, forming heat dissipation fins 1.3 between the grooves, which can increase the heat dissipation surface area. A copper alloy thermally conductive layer can also be pre-embedded inside the heat sink housing to further reduce thermal resistance and ensure that heat is quickly transferred to the external environment.

[0036] The diverter three-way valve is installed on the outside of the heat sink housing and located between the inlet ends of the two cooling channels. The diverter three-way valve uses hydraulic servo drive technology, enabling precise adjustment of the coolant distribution ratio according to instructions from the FPGA control unit. The initial preset state is 70:30, prioritizing motor cooling to ensure optimal motor heat dissipation under normal operating conditions. Under high-temperature conditions, such as ambient temperature > 40℃ or motor load > 80% of rated power, the diverter three-way valve automatically switches to a 50:50 balanced mode, evenly distributing coolant to the cooling channels corresponding to the motor and cycloidal reducer, preventing overheating of any single component. Under extreme load conditions, such as reducer input torque > 120% of rated torque, the distribution ratio is adjusted to 40:60, prioritizing cooling of the cycloidal reducer and focusing on enhancing cooling of the reducer's meshing area to prevent scuffing failure of the cycloidal gear teeth. The diverter three-way valve integrates a high-precision pressure sensor, capable of real-time monitoring of pressure changes within the channels and feeding flow data back to the control system, forming a closed-loop regulation.

[0037] The oil-throwing impeller is integrally formed on the main shaft connecting the motor output end and the cycloidal reducer input end. As the main shaft rotates, it breaks the lubricating oil (the space between the motor output end and the reducer input end in the heat sink housing is filled with lubricating oil) into droplets, which cover the cycloidal wheel tooth surface and the bearing raceway.

[0038] Temperature sensor mounting slots are provided on the outer sides of the two cycloidal wheels 3.1 of the cycloidal reducer, corresponding to the tooth root. Wireless temperature sensors are embedded and fixed (by adhesive bonding) in both mounting slots. These wireless temperature sensors employ wavelength demodulation technology. The wireless temperature sensors can monitor the tooth surface contact temperature in real time. When the temperature exceeds the warning threshold, the system immediately issues an alarm and initiates pre-cooling measures.

[0039] A vibration sensor mounting slot is provided on the inner wall of the planetary carrier 3.2 of the cycloidal reducer near the cycloidal wheel. A triaxial MEMS vibration sensor is embedded and fixed in the mounting slot. The triaxial MEMS vibration sensor captures the meshing frequency of the cycloidal wheel and uses the Fast Fourier Transform (FFT) algorithm to analyze the spectral characteristics of the vibration signal, which can accurately identify abnormal vibrations caused by wear (such as the appearance of non-meshing frequency noise in the frequency components). The vibration data and temperature data are synchronously acquired, filtered, fused, and feature extracted in real time through the FPGA control unit, which can provide early warning of mechanical failures.

[0040] The FPGA control unit is embedded inside the motor end cover. Its core function is to execute a vibration-temperature dual closed-loop algorithm to dynamically adjust the opening of the three-way valve and the power of the cooling pump. The FPGA control unit has a built-in Q-learning reinforcement learning model, which uses temperature uniformity, energy consumption coefficient, and vibration RMS value as reward functions to optimize control parameters (such as PID parameters, three-way valve opening curve, etc.) through online learning.

[0041] The temperature loop employs an incremental PID control algorithm, with the control objective being a temperature difference of ≤5℃ between key components of the motor and reducer. Temperature data is acquired in real-time from a fiber optic Bragg sensor, and the PID calculations are used to output a PWM signal to control the displacement of the three-way valve spool.

[0042] The vibration ring employs an adaptive filtering algorithm based on order analysis. First, it tracks the order of the signals acquired by the triaxial MEMS vibration sensor, extracting the vibration energy of the meshing frequency and its harmonics. When the vibration energy of a certain order exceeds a threshold, the system automatically adjusts the cooling pump power, suppressing the transmission of vibration energy by changing the coolant flow rate.

[0043] The working principle of the integrated temperature control system of cycloidal reducer and motor of this invention is as follows:

[0044] Startup Phase: After the system is powered on, the FPGA control unit first reads the preset initial parameters. The three-way valve distributes the coolant flow at a 70:30 ratio to ensure priority heat dissipation for the motor windings. Simultaneously, the phase change material layer begins to absorb the initial heat load generated during motor startup, and the micro heat pipe array starts synchronously, accelerating heat transfer to the cooling channels. The oil slinger rotates with the main shaft, atomizing the lubricating oil and covering the cycloidal wheel teeth and bearing raceways, establishing initial lubrication. The wireless temperature sensor and the triaxial MEMS vibration sensor begin to collect temperature and vibration data in real time and transmit them wirelessly to the FPGA for preprocessing.

[0045] During steady-state operation, the FPGA control unit updates control commands every 200ms based on the real-time acquired thermal load map (constructed by a temperature sensor network). By dynamically adjusting the three-way valve opening and cooling pump power, the system is always in optimal heat dissipation mode. For example, when the motor load stabilizes at 50% of rated power, if a temperature rise is detected in the reducer meshing area, the FPGA automatically increases the coolant flow to the reducer to 40%-45%, while simultaneously increasing the cooling pump speed to enhance heat dissipation. During this stage, the Q-learning model continuously learns online, constantly optimizing control parameters based on reward function feedback, achieving self-evolution of system performance.

[0046] Overload protection phase: When the system detects an overload, it immediately triggers a graded load reduction protection mechanism. First, the FPGA control unit issues a command to adjust the three-way valve opening to reducer priority mode (40:60) and run the cooling pump at full speed to maximize reducer lubrication. Simultaneously, it sends a load reduction signal to the external control system, categorized into three levels based on the overload severity: Level 1 load reduction (load reduced to 80% of rated value), Level 2 load reduction (load reduced to 60% of rated value), and Level 3 load reduction (shutdown protection). During the load reduction process, temperature and vibration data are continuously monitored. If the parameters return to normal, the system automatically and gradually returns to normal operation; if the abnormality persists, the load reduction state is maintained until the fault is resolved.

[0047] 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 temperature control system integrating a cycloidal reducer and a motor, characterized in that: It includes a cycloidal reducer, heat sink housing, cooling channels, wireless temperature sensor, flow divider three-way valve, motor, FPGA control unit, and triaxial MEMS vibration sensor; The heat sink housing is made of high-strength aluminum alloy and is cylindrical in shape. An inner flange is provided in the middle of the heat sink housing. The part of the inner flange near the inner wall of the heat sink housing forms a motor mounting platform. The motor is fixed to the rear side of the motor mounting platform inside the heat sink housing. The cycloidal reducer is fixedly connected to the front end of the heat sink housing through a flange on its outer shell, so that the cycloidal reducer extends into the front part of the heat sink housing. The heat dissipation housing has two sets of cooling channels built in, one in front and one in back. The front set of cooling channels corresponds to the cycloidal reducer, and the rear set of cooling channels corresponds to the motor. The end closest to the two sets of cooling channels is the inlet end, and the inlet ends of the two sets of cooling channels are respectively connected to the two outlets of the diversion three-way valve. The inlet of the diversion three-way valve is connected to the external cooling pump through a pipeline. Temperature sensor mounting slots are provided on the outer sides of the two cycloidal wheels of the cycloidal reducer at the locations corresponding to the tooth roots. Wireless temperature sensors are embedded and fixed in the sensor mounting slots on both sides. A vibration sensor mounting slot is provided on the inner side wall of the planetary carrier of the cycloidal reducer near the cycloidal wheel, and a triaxial MEMS vibration sensor is embedded and fixed in the vibration sensor mounting slot. The FPGA control unit is embedded inside the motor end cover. Based on the detection values ​​of the wireless temperature sensor and the triaxial MEMS vibration sensor, it runs a vibration-temperature dual closed-loop algorithm to dynamically adjust the opening of the three-way valve and the power of the cooling pump.

2. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The inner flange has an annular groove on the front and rear surfaces near the center of the heat dissipation shell; the annular grooves on both sides are filled with a phase change material layer, which is a graphene-reinforced phase change material, and a micro heat pipe array is pre-embedded in the phase change material layer.

3. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The two sets of cooling channels adopt a variable diameter spiral channel design, with a narrowing inlet section and an expanding outlet section; a nano-ceramic coating is sprayed on the inner wall of the cooling channel.

4. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The diverter valve precisely adjusts the coolant distribution ratio according to the instructions of the FPGA control unit: the initial preset state is 70:30, with priority given to motor cooling; when the ambient temperature is >40℃ or the motor load is >80% of the rated power, the diverter valve automatically switches to a 50:50 balanced mode, evenly distributing coolant to the cooling channels corresponding to the motor and the cycloidal reducer; when the reducer input torque is >120% of the rated torque, the distribution ratio is adjusted to 40:60, achieving priority cooling for the cycloidal reducer; and a high-precision pressure sensor is integrated into the diverter valve.

5. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The FPGA control unit has a built-in Q-learning reinforcement learning model, which uses temperature uniformity, energy consumption coefficient, and vibration RMS value as reward functions to optimize control parameters through online learning. The control parameters include PID parameters and three-way valve opening curve parameters.

6. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The temperature loop in the vibration-temperature dual closed-loop algorithm adopts an incremental PID control algorithm. The control target is that the temperature difference between the key parts of the motor and the reducer is ≤5℃. The temperature is collected in real time by the wireless temperature sensor, and the PWM signal is output after PID calculation to control the displacement of the three-way valve core.

7. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: The vibration loop in the vibration-temperature dual closed-loop algorithm adopts an adaptive filtering algorithm based on order analysis: First, the signal collected by the triaxial MEMS vibration sensor is subjected to order tracking to extract the vibration energy of the meshing frequency and its harmonic components; when the vibration energy of a certain order exceeds the threshold, the system automatically adjusts the cooling pump power to suppress the transmission of vibration energy by changing the coolant flow rate.

8. The integrated temperature control system for the cycloidal reducer and motor according to claim 1, characterized in that: An oil slinger is integrally formed on the main shaft that connects the motor output end and the cycloidal reducer input end.

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