Encoder with motor thermal protection and motor thermal protection system
By integrating a temperature sensor into the encoder, the complexity and structural limitations of traditional motor overheat protection methods are solved, achieving efficient thermal protection for small motors and reducing hardware costs and resource consumption.
Patent Information
- Application Number
- CN202423253000.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2034-12-27
AI Technical Summary
Traditional motor overheat protection methods require real-time communication between the temperature signal acquisition controller and the motor control system, which increases cable complexity and cost. Furthermore, small motors cannot be equipped with temperature signal acquisition controllers due to structural size limitations.
The temperature sensing function is integrated into the encoder. The encoder CPU and hardware resources are used to process and acquire temperature signals. The communication bus is used to transmit position and temperature data, avoiding additional cables and hardware upgrades.
It simplifies the design of motor thermal protection, reduces system hardware costs, avoids hardware upgrades and resource consumption, is suitable for small motors, and improves protection effectiveness.
Smart Images
Figure CN223666193U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to encoder technical field, especially relate to a kind of encoder and motor thermal protection system with motor thermal protection. BACKGROUND
[0002] Encoder is a kind of sensor device that converts rotary displacement or linear displacement into electrical signal, mainly applied in motor position feedback control system, installed on the rotor output shaft of the rear end of motor.
[0003] Due to the continuous development of insulation technology, both the output torque and the volume of motor are required to be reduced in design, so that the thermal capacity of new motor is smaller and the overload capacity is weaker. And due to the improvement of production automation, the motor is required to run frequently in the mode of starting, braking, forward and reverse rotation and variable load, so that the motor is more likely to overheat or fail in temperature control when overload, open phase, locked rotor, short circuit, overvoltage, undervoltage, leakage, three-phase imbalance, bearing wear and eccentricity occur.
[0004] Since the winding coil of motor is made of enameled wire, the enameled wire has a thin layer of insulating paint on the outer surface of the wire, which is the weakest link in the entire motor insulation. Therefore, the temperature rise of motor has the greatest impact on the winding part. Figure 1 As shown in the drawings, the conventional method for motor overheat protection is to embed a small volume sensor, PTC thermistor or thermocouple temperature sensing head, in the winding of motor stator, install temperature signal acquisition controller at the rear end of motor shell, and connect the signal line of PTC thermistor or thermocouple temperature sensing head to temperature signal acquisition controller. Temperature signal acquisition controller includes power supply system, signal processing and acquisition circuit, CUP logic controller, industrial bus communication interface and temperature signal input interface. During the operation of motor, PTC thermistor or thermocouple temperature sensing head feeds back the temperature electrical signal of motor stator winding to temperature signal acquisition controller, and temperature signal acquisition controller converts the temperature electrical signal into corresponding temperature value and transmits it to motor control system through signal cable.
[0005] Under normal circumstances, the temperature sensor for motor overheat protection is in low resistance state, which does not affect the normal operation of motor. When the motor overheats due to internal failure, the temperature sensor for motor overheat protection changes in resistance value or thermoelectric force, and the temperature rises sharply. When the motor control system receives the temperature data from temperature signal acquisition controller, the control system unit loses power and releases, and the motor stops running, waiting for troubleshooting and re-running.
[0006] The traditional motor overheating protection method needs real-time communication between the temperature signal acquisition controller and the motor control system, at least 4 cables including power supply and serial communication line need to be added between the communications, the cables need to be shielded, the technical solution has high complexity, and the cost of the temperature signal acquisition controller needs to be increased; and the motor control system needs to add an industrial bus communication interface to read the temperature value, occupying the CPU and hardware resources of the motor control system. In addition, small motors have no space to install temperature signal acquisition controllers due to the limitation of the shell rear end shape structure size, and the traditional method cannot be used for small motors. Practical new type content
[0007] Therefore, the utility model provides a kind of encoder and motor heat protection system with motor heat protection, temperature sensing function is integrated in encoder, temperature signal processing and acquisition function are realized by encoder CPU (controller) and hardware resources, solve the problems of high structural complexity, occupying motor control system resources and being limited by motor shape structure size in traditional motor internal design temperature control system.
[0008] To achieve the above object, the technical scheme of the utility model is as follows:
[0009] The utility model provides a kind of encoder with motor heat protection, comprising: the encoder body of acquisition position data, temperature signal line, temperature sensor and controller;
[0010] Wherein, temperature signal line is used to connect temperature measuring component in motor stator winding;Temperature signal line is communicated with temperature sensor, temperature sensor is used to filter, shape and analog-digital conversion transmission signal of temperature signal line;Temperature sensor is communicated with controller, and controller is used to receive and / or acquire temperature signal output by temperature sensor, and temperature data is fed back to motor control system.
[0011] Preferably, temperature signal line is 2.
[0012] Preferably, temperature sensor includes filter shaping circuit and ADC acquisition circuit.
[0013] Preferably, controller is also used to receive and / or acquire position data.
[0014] Preferably, it further includes: communication bus for transmitting position data and temperature data to motor control system.
[0015] The utility model provides a kind of motor heat protection system, comprising:
[0016] Motor, motor control system, motor control line and encoder with motor heat protection;
[0017] Temperature measuring components are installed in the stator windings of the motor.
[0018] An encoder with motor thermal protection is installed on the motor output shaft to collect the motor's position and temperature data. The position and temperature data are fed back to the motor control system via a communication bus, and the motor control system controls the motor power supply through the motor control line.
[0019] Preferably, the temperature sensing component is a PTC thermistor or a thermocouple temperature sensor.
[0020] Preferably, the encoder with motor thermal protection has a temperature over-limit function via a communication bus.
[0021] Preferably, position data and temperature data are transmitted to the motor control system via a communication bus using a bus protocol.
[0022] Compared with the prior art, the present invention can achieve the following beneficial effects:
[0023] This invention incorporates a thermal protection temperature sensor for the motor within the encoder. This innovative design solves the problem of temperature acquisition and control difficulties in small motors due to size limitations, providing an effective solution for thermal protection of small motors. Furthermore, with the integrated temperature sensor function, temperature and position data share a communication bus. Communication between the encoder and the motor control system eliminates the need for additional signal cables and bus communication interfaces, effectively reducing system hardware costs. The temperature signal acquired by the PTC thermistor or thermocouple temperature sensor is processed and converted by the encoder's internal controller and hardware resources, without consuming the motor control system's CPU or hardware resources. For motor control systems without pre-installed temperature data acquisition, no hardware upgrades are required. The system only needs to add a software module to acquire temperature data to achieve motor thermal protection, eliminating the need for hardware upgrades or motor replacement for existing motors without thermal protection. During encoder-motor assembly, only the temperature signal line needs to be connected to the encoder, avoiding the need for secondary assembly of the thermal protection temperature module in the industrial motor control system, simplifying the assembly process.
[0024] In addition, encoders mounted on motors typically have a high level of protection, and temperature sensors integrated into the encoder are well protected, avoiding damage caused by insufficient protection in industrial settings. Attached Figure Description
[0025] The accompanying drawings, which form part of this invention, are used to provide a further understanding of this invention. The illustrative embodiments and descriptions of this invention are used to explain this invention and do not constitute an undue limitation of this invention. In the drawings:
[0026] Figure 1 This is a block diagram of a traditional motor overheat protection design scheme in the background technology;
[0027] Figure 2 This is a structural block diagram of an encoder with motor thermal protection provided according to an embodiment of the present utility model;
[0028] Figure 3 This is a block diagram of the motor thermal protection system provided according to an embodiment of the present utility model. Detailed Implementation
[0029] To make the purpose, technical solution, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and do not constitute a limitation thereof. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this utility model. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, some operations related to this utility model are not shown or described in the specification. This is to avoid obscuring the core parts of this utility model with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.
[0030] It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other to form various implementation methods. Furthermore, the steps or actions in the method description can be rearranged or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various orders in the specification and drawings are merely for the clear description of a particular embodiment and do not imply a mandatory order, unless otherwise stated that a particular order must be followed.
[0031] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0032] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0034] Please see Figure 2In one embodiment of this utility model, an encoder with motor thermal protection is provided to solve the problems of complex hardware structure, high resource consumption in motor control system, and limitation by motor size in traditional thermal protection schemes. More importantly, traditional schemes require hardware upgrades to the motor or motor control system, which may lead to the need to replace the motor or motor control system, resulting in high hardware upgrade costs and potential resource waste. The encoder with motor thermal protection proposed in this utility model embodiment can be directly applied to existing motor systems, effectively reducing hardware upgrade costs. Specifically, the encoder mainly includes: an encoder body, a temperature signal line, a temperature sensor, and a controller. The encoder body is the core component of a traditional encoder, which converts the position or linear displacement of a rotating component into digital pulse signals for counting angular displacements and outputting position data. Different types of encoders have different functional components. Taking a traditional photoelectric encoder as an example, it typically includes a code disk, a reading head, a main shaft, a reading circuit, and an encoder controller (CPU). The encoder body is a traditional design, and this utility model embodiment does not improve upon it; therefore, it will not be described in detail.
[0035] The temperature sensor is located inside the encoder and connects to both the encoder's temperature signal line and the controller. Two additional temperature signal lines are added to the traditional encoder signal cable. One end of each line connects to the temperature sensor, and the other end connects to a temperature sensing component embedded in the motor stator windings. This component typically uses a very small PTC thermistor or thermocouple temperature sensor. A PTC thermistor is a positive temperature coefficient thermistor, meaning its resistance increases with temperature. At room temperature, its resistance is relatively low, but it increases significantly when heated above a certain temperature by an external heat source. A thermocouple temperature sensor converts temperature changes into an electrical signal. The temperature sensing component can acquire the temperature of the motor stator windings in real time. At different temperatures, the component outputs a corresponding signal via the temperature signal line, typically expressed as a voltage value.
[0036] After the signal collected by the temperature sensing component is transmitted to the temperature sensor via the temperature signal line, the temperature sensor needs to process the signal. Specifically, the temperature sensor includes a filtering and shaping circuit and an ADC (analog-to-digital converter) acquisition circuit. The raw signal received by the temperature sensor needs to be filtered and shaped by the filtering and shaping circuit to reduce noise and interference. The shaped signal is then sent to the ADC acquisition circuit, which converts the analog signal into a digital temperature signal. The ADC acquisition circuit then transmits the converted digital signal to the encoder controller, which is the CPU for position data acquisition and processing. The temperature signal processed by the temperature sensor and the position data share the controller. The controller calculates the corresponding temperature data based on the characteristic curve of the PTC thermistor or thermocouple temperature sensor (usually a lookup table or formula pre-set in the encoder firmware). The controller is used to transmit the collected temperature data and position data to the motor system controller via the communication bus in the form of a bus protocol. While the encoder controller reads the encoder position data in real time to control the motor, it also obtains the real-time temperature rise information of the motor through the temperature sensor inside the encoder, which plays a role in the thermal protection function of the motor. Typically, the measuring temperature range of this encoder is -40-200℃, with an error within ±3℃.
[0037] Based on the encoder with motor thermal protection described above, please refer to... Figure 3 This utility model embodiment also provides a motor thermal protection system, including: a motor, a motor control system, a motor control line, and the aforementioned encoder with motor thermal protection. The encoder with motor thermal protection is installed on the output shaft of the motor and is used to control and count the motor. The principle and process of the encoder body acquiring the position data of the motor output shaft are existing technologies and will not be described in detail here.
[0038] The motor control system controls motor speed, torque, and power-on / off states. It supplies power (three-phase UVW) to the motor via motor control lines and drives its rotation. One end of the encoder's two temperature signal lines is connected to an internal temperature sensor, and the other end is connected to a temperature sensing component such as a PTC thermistor or thermocouple in the motor stator windings. The sensor filters and shapes the signal collected by the sensing component before feeding it into an ADC (Analog-to-Digital Converter) circuit. The ADC circuit converts the analog signal into a digital signal, and the encoder controller calculates the corresponding temperature data using a lookup table or formula. This temperature data, along with the position data, is then fed back to the motor control system via a communication bus using a bus protocol. The motor control system can also obtain the current temperature data via the communication bus through a query mechanism.
[0039] The encoder with motor thermal protection has a temperature over-limit function via a communication bus. The motor control system can set the encoder's temperature over-limit function to be enabled or disabled through the bus protocol interface, and can also customize the temperature over-limit threshold. When the temperature over-limit function is enabled, the encoder's temperature over-limit alarm will be set to notify the motor control system when the current temperature reaches the set threshold.
[0040] During motor operation, the temperature sensor inside the encoder reads the temperature data of the PTC thermistor or thermocouple temperature sensor in real time to monitor the temperature rise of the motor. When the motor overheats due to a fault, the temperature rises sharply. When the temperature read by the motor controller reaches the set threshold, the motor control line is de-energized and the motor stops running.
[0041] The encoder with motor thermal protection provided in this embodiment has a temperature sensor. When applied to a motor thermal protection system, it simplifies the thermal protection design of traditional motor systems. Based on the original system, motor thermal protection can be achieved without hardware changes to the motor and motor control system. Furthermore, the temperature sensor is located inside the encoder, which reduces the space requirements for motor installation in the thermal protection design and provides a solution for the spatial constraints of thermal protection for small motors.
[0042] In summary, the above description is merely a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.
[0043] The systems, apparatuses, modules, or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, a computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or any combination of these devices.
[0044] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0045] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.
[0046] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.
Claims
1. An encoder with motor thermal protection, comprising an encoder body for acquiring position data, characterized in that, Also includes: Temperature signal lines, temperature sensors, and controllers; The temperature signal line is used to connect to the temperature measuring component in the stator winding of the motor; the temperature signal line is connected to the temperature sensor, which is used to filter, shape, and perform analog-to-digital conversion on the transmitted signal of the temperature signal line; the temperature sensor is connected to the controller, which is used to receive and / or acquire the temperature signal output by the temperature sensor and feed the temperature data back to the motor control system.
2. The encoder with motor thermal protection as described in claim 1, characterized in that, There are two temperature signal lines.
3. The encoder with motor thermal protection as described in claim 1, characterized in that, The temperature sensor includes a filtering and shaping circuit and an ADC acquisition circuit.
4. The encoder with motor thermal protection as described in claim 1, characterized in that, The controller is also used to receive and / or acquire position signals.
5. The encoder with motor thermal protection as described in claim 4, characterized in that, Also includes: A communication bus used to transmit position and temperature data to the motor control system.
6. A motor thermal protection system, characterized in that, include: The motor, the motor control system, the motor control line, and the encoder with motor thermal protection as described in any one of claims 1 to 5; Temperature measuring components are installed in the stator windings of the motor. The encoder with motor thermal protection is installed on the motor output shaft and is used to collect the motor's position and temperature data. The position and temperature data are fed back to the motor control system through the communication bus. The motor control system controls the power supply to the motor through the motor control line.
7. The motor thermal protection system as described in claim 6, characterized in that, The temperature measuring component is a PTC thermistor or a thermocouple temperature sensor.
8. The motor thermal protection system as described in claim 6, characterized in that, The encoder with motor thermal protection is equipped with a temperature over-limit function via a communication bus.
9. The motor thermal protection system as described in claim 6, characterized in that, Position data and temperature data are transmitted to the motor control system via a communication bus using a bus protocol.