6 days ago •
Widely used in many industries and having strong practicability, the planetary reducer covers a wider range of applications. Today, let’s talk about the advantages and application industries of planetary reducers, so that everyone can better understand this product.
The Advantages of a Planetary Reducer
1. Improving the efficiency of operation
The planetary reducer can be used together with the servo motor to increase the torque. Therefore, increasing the speed of the servo motor doubles the power density of the entire servo system. It can well improve the operating efficiency of the entire mechanical equipment.
- Increasing the output torque
- High precision and heavy load
In ordinary mechanical operation, if we want to increase the output torque of the servo motor, we have to choose a high-power servo motor, which is not only expensive, but also requires a relatively strong structure of the motor, so if we want to increase the torque, we can use a planetary reducer for its relative low price and satisfying effects.
Planetary reducers can be used when high-precision positioning is required and need to load heavily. In some industries such as robotics, medical and military industries, it is commonly featured by the torque required by itself actually exceeding that of a servo motor. So this problem can be well solved by planetary gear reducer.
The Application of a Planetary Reducer
Planetary reducers are widely used in many industries such as construction machinery, medical equipment, instrumentation, automobiles, construction machinery and other industries. It is also expected that the planetary reducers can make a great difference to more industries.
6 days ago •
1. the worn planetary gear tooth and gluing, pitting, grinding deviation and introduction (especially the pinion speed is very easy to wear) may cause vibration of the reducer.
Treatment: timely replacement of severely worn gears. Generally can use the reverse running method to solve the tooth surface serious gluing.
2.the planetary reducer gears of the meshing surface contact and uneven force, so that the axial movement of the gear frequently, the occurrence of tooth fracture or tooth ring fracture, as well as spoke cracks, etc., causing vibration of the reducer.
Treatment: replace the damaged parts; adjust the gear ring and spoke door with; replace the gear of tooth wear over limit; adjust the bearing clearance; improve gear lubrication, etc.
3. planetary reducer high-speed shaft and medium-speed shaft slide key wear introduced, shaft pinion coupling bolts have loosened or fracture caused by reducer vibration.
Treatment: replace the sliding keys and broken bolts, tighten the loose bolts.
4. planetary reducer gear rough machining and shaft and bearing wear, in normal operation, the tooth ring non-working surface stress, causing vibration of the reducer.
Treatment: replace the parts that meet the processing accuracy and roughness requirements; remove the worn shaft and bearings.
5. planetary gears and shaft with a large amount of interference, so that the shaft breaks at the fit caused by the vibration of the reducer.
Treatment: replace the broken shaft, adjust the gear and shaft with the amount of interference.
6. planetary gear and shaft shaft hole fit tolerance such as hole is too large, resulting in gears and shafts are not concentric, or gears and shafts are not properly assembled to produce loose phenomenon, causing vibration of the reducer.
Treatment: adjust the gear and shaft shaft hole fit tolerance; careful assembly to prevent loosening.
7. planetary reducer output shaft gear wheel center and ring loosening, side pressure plate activities or pressure plate bolts have loose or broken, as well as the large gear static balance or unbalance, causing vibration of the reducer.
Treatment: tighten the wheel center and tooth ring; tighten the pressure plate bolts, replace the broken bolts; improve the balance of the large gear.
6 days ago •
Automatic control systems are classified by the structural characteristics of the system and can be divided into open-loop control systems and closed-loop control systems. What is the difference between these two, this article will introduce them to you.
I. Open-loop control system
Between the control device and the controlled object, there is only a cis-action and no reverse link, the system neither needs to measure the output quantity, nor needs to feed it back to the input to compare with the given input quantity, so the input quantity of the system is the given value of the system.
The open-loop control system, on the other hand, is characterized by the fact that there is no link in the system and the action signal is transmitted from input to output in a single direction.
Characteristics of open-loop control system.
*There is no feedback link in the system, no feedback measuring element is needed, so the structure is simpler and lower cost.
*The system works in open loop and has good stability.
*The system can not achieve the role of automatic adjustment, the error caused by interference can not be self-corrected, so the control accuracy is not high enough.
Therefore, the open-loop control system is suitable for applications where the relationship between the input and output quantities is fixed and the internal and external disturbances are small. In order to ensure a certain control accuracy, the open-loop control system must use high-precision components.
2. Closed-loop control system
It sends the output quantity of the controlled object back to the input and compares it with the given input quantity to form a deviation signal, which acts on the controller to make the output quantity of the system converge to its desired value.
Closed-loop control system is characterized by the presence of feedback links in the system, the role of the signal according to the closed-loop transfer, the system's output has a direct impact on the role of control.
Closed-loop control systems have the following characteristics compared to open-loop control systems.
*the system has a negative feedback link, can automatically adjust the output amount of compensation, the perturbation caused by changes in the parameters in the system and the system outside the perturbation, have a certain anti-interference ability.
*The system uses negative feedback, in addition to reducing system errors and improving control accuracy, it can also accelerate the transition process of the system, but the control quality of the system is related to the accuracy of the feedback element.
*The system works in closed loop, which may produce instability, so there is a stability problem.
Closed-loop control system since the interference, the use of negative feedback auto-adjustment role, can effectively suppress everything is wrapped in the negative feedback loop on the forward channel of the perturbation effect on the controlled quantity, and can closely follow the given role, so that the broken control quantity in accordance with the changes in the given signal and change, so as to achieve complex and accurate control. Therefore, this, closed-loop control system is also often called automatic regulation system, the controller in the system is also often called regulator.
01/20/2023 at 07:35 •
How to Set the Subdivision of the Digital Stepper Driver
- In the terms of setting the value of a digital stepper driver, the higher the subdivision value, the higher the control resolution on common sense. For two-phase motor, the calculation method of pulse equivalent is as follows: pulse equivalent = lead screw pitch ÷ subdivision number ÷ 200.
- Takeoff Speed: This parameter corresponds to the take-off frequency of the stepper motor, meaning that the motor can start working without acceleration. The proper selection of this parameter can improve the processing efficiency and avoid the low-speed section with poor motion characteristics. However, the value is set too large, it will cause stuffy cars. So a margin must be left.
- Uniaxial acceleration: Used to describe the acceleration and deceleration capacity of a single feed shaft. This index is determined by the physical characteristics of the machine tool, such as the quality of the moving part, the torque of the feed motor, resistance, cutting load, etc. The greater this value, the more efficient it will be, meaning the less time will be spent in acceleration and deceleration during exercise. General speaking, in terms of stepper motors, this value should between 100 and 500. While for servo motors, it can be set between 400 and 1200. When setting, the value should small and the motor should do repeated exercise for a while. Pay attention to it. If no abnormalities can be observed, then the value can be increased. If any abnormalities are found, the value should be reduced and leave a 50%~100% insurance balance.
- Bend acceleration: Used to describe the acceleration and deceleration capabilities of multiple feed axes when they are in motion. It determines the speed of the machine tool in circular motion. The larger this value is, the higher the allowable speed of the machine tool in circular motion is. The value of lathe which is consisted of stepper motors should kept within 400 to 1000. And the value of servo motors should be 1000 and 5000. If it is a heavy lathe, the value should be adjusted smaller. When setting, the value should small and the motor should do repeated exercise for a while. Pay attention to it. If no abnormalities can be observed, then the value can be increased. If any abnormalities are found, the value should be reduced and leave a 50%~100% insurance balance.
- According to the position where the three null-point sensors are installed, the user can set the parameter to return back to the mechnical origin. When the user sets correctly, he can run the Operation menu.
- Setting the automobile refueling parameters and judging whether it is right. If it is correct, the parameters should be adjusted to meet the practical demand.
- Then the user should judge whether the setting value of the electronic gear matches that figure of pulse equivalence. The user can make a mark on any axis of the machine tool, which can be seen as the working zero point. By inputting the command directly, jogging or manual operating, the axis can move a fixed distance. A vernier caliper can be used to measure whether the actual distance is consistent with the distance displayed in the software.
- The last step is to measure whether there is pulse loss. The user can adopt a method like this: he can use a sharp knife to mark a point on a semi-finished product and set the point as the origin. The Z axis should be raised and set to 0. And then make the lathe exercise repeatedly. But be careful, the practical speed of these three axes should be limited.
01/20/2023 at 07:34 •
As an operating element of mechanical equipment, servo motors get widely used in the servo systems. Sometimes the heating of the operating servo motors may make us a wonder whether it is normal if we lack some professional knowledge. Actually, it is a widespread phenomenon that motor cause heat when working. But overheating needs our attention to reduce its temperature.
The temperature which the motor can be reached depends on the insulation. General speaking, the motor will not be damaged unless the internal temperatures is higher than 130 C and the outer temperature should below 90 C. Therefore, 70-80 C of the outer side of motor is the normal temperature. Except for the thermometer to measure, we can also distinguish by hand. If we can touch it for 1-2 seconds, then the temperature should within 60C. If we can touch it for less than 1 second, the temperature should be about 70-80 C. And if we drip some drops of water on it, the vaporization of water activation collateral clarifies that the temperature is above 90 C. Of course, we can also use a professional thermometer to test.
According to the principle of the server motor, to reduce the overheating is to reduce the copper loss and iron loss. There are two ways to reduce copper loss, reducing resistance and reducing current, which demands us to select the motor with lower current. In the terms of two-phase motor, we have better select series motor. But this usually conflicts with requests for moments and speeds. For the currently selected motor, the active half-current operation function of the driver and the offline function should be fully utilized. But there are not many ways to reduce the iron loss. The voltage level is related to the iron loss. So when we select an appropriate motor, its high speed, stability, heat, and noise should also be considered.
The heating of motors is a normal situation. As long as the temperature is not too high, there is no need to worry about that.
01/20/2023 at 07:33 •
The digital stepper driver is an executing mechanism that can convert the electrical pulse signal it is subjected to into angular displacement. When it receives an electronic pulse signal, it will rotate by a fixed angular displacement in a direction set previously.We can control the angular displacement by controlling the number of pulses it sends, so as to achieve the purpose of accurate positioning. By the control of the frequency of its pulse signal, the speed and accelerated speed of the motor can be controlled, so as to achieve the purpose of speed adjustment and positioning.It is widely used in a variety of large and medium-sized numerical control devices with high resolution, such as carving machines, crystal grinders, medium-sized numerical control machines, electroencephalographic embroidery machines, packaging machines, springs, dispensers, cutting and feeding systems, etc.
The phase of a stepping motor refers to the number of coil groups inside the stepping motor. General speaking, there are two-phase motors, three-phase motors, four-phase motors and five-phase motors. The different phases will result in a different step angle.The step angle of a common two-phase step motor is 1.8 degrees, three-phase is 1.2 degrees, and five-phase is 0.72 degrees. Not equipped with a subdivision driver, the user mainly relies on selecting different phases of the stepping motor to satisfy the request of the step angle. If a subdivision drive is used, the phases will become no use in that the use can directly change the step angle on the drive.
The subdivision of the stepping motor driver will result in a qualitative leap in the motor's performance, but all of this is generated by the driver itself and is independent of the motor and control system. When in operation, the only thing that users need pay attention to is the change of the step angle, which exerts an influence on the frequency of the signal sent by control system. Since the step angle of the stepping motor will become smaller after subdivision, the frequency of the step signal should be improved accordingly. Taking the 1.8 degree of the stepping motor as an example, the angle is 0.9 degrees when it is in half-step state, and 0.18 degrees when it is in ten-segment state. On the condition that the motor rotate at the same speed, the frequency of the step signal sent by the control system is 5 times of that in ten-segment state.
The accuracy of ordinary stepping motor is 3~5% of the step angle. The single-step deviation of the stepping motor does not affect the accuracy of the next step, so the accuracy of the stepping motor is not accumulated.
12/27/2022 at 00:54 •
There are several factors to consider when choosing a variable frequency drive (VFD) for your application:
Motor power and voltage: You will need to ensure that the VFD is rated for the power and voltage of the motor you are using.
Control method: VFDs can use different control methods, such as voltage control, current control, and flux control. Choose the method that is best suited to your application.
Frequency range: The VFD should have a frequency range that covers the desired operating speed of the motor.
Environmental conditions: Consider the environmental conditions in which the VFD will be used, such as temperature, humidity, and exposure to dust and dirt.
Protection features: Look for VFDs with protection features such as overvoltage, undervoltage, overcurrent, and short circuit protection.
EMI/RFI filters: If you are using the VFD in an environment where electromagnetic interference (EMI) or radio frequency interference (RFI) is a concern, you may want to consider a VFD with EMI/RFI filters.
Size and weight: Make sure the VFD is the appropriate size and weight for your application.
Cost: Determine your budget and choose a VFD that meets your needs within that budget.
It is also a good idea to consult with a knowledgeable sales representative or a technical expert to ensure that you choose the right VFD for your specific application.
12/27/2022 at 00:53 •
There are several factors to consider when choosing a servo motor:
Torque: The torque requirement of the application should be matched with the motor's maximum continuous torque rating. It is important to select a motor that can deliver enough torque to power the load without overheating or stalling.
Speed: The speed requirement of the application should be matched with the motor's maximum speed rating. It is important to select a motor that can operate at the desired speed without overheating or losing accuracy.
Size and weight: The size and weight of the servo motor should be appropriate for the application. A larger, heavier motor may be more suitable for applications that require high torque, but a smaller, lighter motor may be more suitable for applications that require faster speeds or precise positioning.
Voltage and current: The voltage and current requirements of the servo motor should be compatible with the power supply available. It is important to select a motor that can operate at the available voltage and current without overheating or losing accuracy.
Feedback: The servo motor should have a suitable feedback mechanism, such as an encoder or resolver, to provide precise position and speed control.
Mounting: The servo motor should have a suitable mounting configuration for the application, such as a flange or shaft mount.
Environment: The servo motor should be suitable for the operating environment, including temperature, humidity, and vibration.
It is often helpful to consult with a manufacturer or supplier to determine the most suitable servo motor for a specific application.
12/27/2022 at 00:49 •
A servo motor is a type of rotary actuator that is used to control the angular position of a shaft. It consists of a motor, a control circuit, and a feedback mechanism.
Here's how it works:
The control circuit receives a command signal from an external controller, which specifies the desired angular position of the shaft.
The control circuit sends a pulse width modulated (PWM) signal to the motor, which controls the speed and direction of the motor.
The motor rotates the shaft to the desired position.
The feedback mechanism, typically a rotary encoder or a potentiometer, measures the actual angular position of the shaft and sends a feedback signal back to the control circuit.
The control circuit compares the feedback signal to the command signal and adjusts the PWM signal as needed to correct any errors and bring the shaft to the desired position.
Servo motors are often used in applications where precise control of movement is required, such as in robotics, aircraft control systems, and factory automation. They are also commonly used in hobby projects, such as radio-controlled vehicles and model airplanes.
11/25/2022 at 07:47 •
The main purpose of servo motors is to control the displacement and operation of the motor equipment. As the commonly used motors, servo motors enjoy the advantages of precise positioning, which results in a wide application.
1.The Main Functions
(1)The servo motor itself also has function of generating a pulse current. Each rotation of an angle will emit a corresponding number of pulses that can be used by servo motors to form a response and a closed loop. In this way, the system can know the number of pulses it has already sent to the servo motor and how many pulses it has already received at the same time, through which it can control the rotation precisely and the positioning precision can reach 0.001mm.
(2)DC servo motor can be divided into brushed motor and brushless motor. In terms of brushed motor, it has edges in low cost, simple structure, large starting torque, wide speed range and easy control. But it needs to change carbon brushes. Although the change has no difficulty, it will cause electromagnetic interference and is burdened with environmental requirements. Therefore, it can be applied in common industry and civil applications that are sensitive to the costs.
(3)While brushless motors are featured by small size, light weight, great output, fast responding speed, small inertial, and stable rotation and torque. It is complex to control, but it is easy to be intelligent. Commutated by square wave and sine wave, the electronic commutation is flexible. The motor is free from maintenance and enjoys a high efficiency, low working temperature, subtle electromagnetic radiation, and a long service time. Besides, it can be applied in any environment.
(4)The AC servo motor can be divided into a synchronous motor and an asynchronous motor. Currently, the former is often applied in motion control. It has a large power range and can work with large power. With low maximum RPM and inertial which will rapidly decreases with the increase of power. Therefore, it is used in what requires low speed and stable operation.
(1)Having extraordinary response speed, the servo motor provides a large torque in the point-to-point fast positioning motion occasion, which makes the system have a extremely high dynamic response and greatly exceeds the limit of the traditional stepping system.
(2) The servo motor remains in the range of its rated speed range and belongs to constant torque output. And it has a variety of feedback adjustments to ensure the running accuracy of the servo motor and output torque.
(3)The Main Applications
*Machinery industry:machining centers, CNC punching machines, bending machines, shearing machines, PLC program controllers, etc.;
*Printing industry:drying board machine; printing machine, offset printing machine, rotary machine, laser phototypesetting, proofing equipment, automatic punching and inkjet printing machine, etc.;
*Medical industry:monitor, B-ultrasound machine, CT control box, electrocardiogram ( EEG) tester, X-ray machine, etc.;
*Food industry: sterilizer, homogenizer, labeling machine, can making machine, flow control instrument, sealing machine, etc.;
*Rubber tire industry: steel wire belt ply production line, inner liner extrusion production line, steel wire calender, etc.;
*Elevator industry: door control, floor control, etc.
11/25/2022 at 07:41 •
Both stepper motors and servo motors are servo units for motion control purposes, which can precisely control the location and speed of motion mechanisms.To adapt to the development trend of digital control, stepper motors or all-digital motors are mostly hired as executive motors in motion control systems, which are widely used in the era of labor saving. Despite the similarity in position controlling, namely pulse train and direction signal, both two motors greatly differ in performance and application.
1.Different Control Precision
The step angle of the two-phase hybrid stepper motor is generally 1.8°, and the step angle of the three-phase hybrid stepper motor is 1.2°.There are also some high-performance stepper motors with smaller step angles. After using subdivision drive technology, the control precision get enhanced so that the number of steps the two-phase hybrid stepper motor can distinguish is about 51200 steps/rev. There are also some motors with higher precision, but their cost will be more.
The control precision of AC servo motors is guaranteed by the rotary encoder at the rear end of the motor shaft. For a servo motor with a standard 2500 line encoder, its pulse equivalent should be 360°/10000=0.036°due to the adoption of quadruple frequency technology.
It is worth noting that a considerable number of people think highly of the precision of AC servo motors, which is actually a misinterpretation. Even with 100 times electronic gear or 30000 line encoder, it will make no difference if the servo motor cannot distinguish that small step. The feedback of encoder is nothing more than making the servo driver align it teeth repeatedly.
Compare with the vast majority of users, the stepper servo motors possess the highest physical precision in terms of the mechanical transmission precision or positioning precision of photoelectric sensor. It is unnecessary to pursue the highest precision in single aspect.
2.Different Overload Capacity
Stepper motors are not able to address overload, while AC servo motors own abilities to address overload and torque overload at 2 to 3 times, which can be used to overcome the inertial torque when starting the inertial overload. Without this ability, the torque of overload and movement characteristics should be taken into consideration when you select the type of motors.
3.Different Operating Performance
The stepper motors control in a open-loop way, where situations including step loss or stalling will easily occur when its starting frequency is too high or its load is too large. Therefore, acceleration and deceleration control program need to be handled in order to ensure its control precision.However, the AC servo motors adopts a closed-loop way. The driver can directly sample the feedback signal of the motor encoder and form position loop and speed loop inside, which makes its control more reliable. Generally, there will be no step loss or overshooting.Besides, the servo driver can automatically rectify lost pulse and give feedback on time to the controller when it is blocked. However, the stepper motor must use sufficient torque margin to avoid stalling.
4.Different Speed Response Performance
It takes 100-2000 milliseconds for a stepping motor to accelerate from a standstill to a working speed (generally several hundred revolutions per minute). With better acceleration performance, it only takes a few milliseconds for the AC servo motors to accelerate from a standstill to its rated speed of 3000RPM, which can be applied in occasions requiring fast start and stop.
In one word, the AC servo motor is superior to stepper motor in terms of some aspects. However the latter will not be replaced wholly due to it unique characteristics.
11/25/2022 at 07:33 •
Adopting frequency conversion technology and microelectronics technology, Variable-frequency Drive, a kind of power control, changes its working power frequency in order to control AC motor.
The VFD is mainly composed of rectification (AC to DC), filter, inverter (DC to AC), braking unit, drive unit, detection unit, micro-processing unit, etc.
Dependent on switching on or off internal IGBT, the VFD can adjust the voltage and frequency of output power supply. For the purpose of energy saving and speed adjustment, it can provide the power and voltage needed in accordance with practical demand of motors. Besides, it also supports many protection functions to avoid terrible consequences caused by overcurrent, overvoltage, overload and so on.
The working principle of VFD is to adopt circuit control to control main circuit, whose rectifier converts AC power into DC power that will be filtered and smoothed in DC intermediate circuit. Then the inverter finally converts the DC power into AC power of the required frequency and voltage. Some VFD will also add CPU and other components to perform necessary torque calculations.
The VFD is an electrical device that can convert power frequency into any frequency and any voltage, which is used to adjust the power and speed of motors. It can be divided into 2 parts: the control circuit and main circuit, and the latter is composed of rectifiers and inverters.
The power frequency of VFD is generally 50Hz or 60Hz, and its frequency and voltage remains the same regardless of being applied in domestic use or production use. Those motors which work at power frequency will cause power loss when adjusting speed. While after the adjustment of VFD, the motor can reduce loss.
As the requirement of industrial automation becomes enhanced and advocacy of energy conservation is prevailing , the VFD get an increasing application, such as in frequency conversion energy saving, automation system, improvement of crafting products qualities and motor soft starting.
10/27/2022 at 01:27 •
As the society develops and advances, mechanization has gotten wide application in production and daily life. Playing an indispensable role in machinery, the DC gear motor has been applied to in wider and wider fields in that whatever demand rotation is in the need of it.
The motor functions as a tool to support and reduce friction, so its quality of accuracy and voice is directly related to the use and life of the machine. However, despite of adopting the DC gear motor with the best performance or imported motor, many customers still suffer from a disappointing efficiency. How to make the most of and select the motor remains the key. Someone may say, “I am just responsible for meeting customers’ demands, and its customers’ own business to use and select a DC gear motor.” But a qualified seller should be doctor-type one who should master both professional knowledge and the use of products in order to recommend the most suitable motor in accordance with the quality of customers’ supporting products and conditions of DC or micro-motor bearings. This is a prevalent way of specialized manufacturing and selling in global major corporation, which has also achieved good performance of since the implementation in Groups concerning people.
A new type of a DC gear motor, called brushless DC gear motor, develops with progress of micro gear motor and microprocessor technology, application of new power electronic devices with higher switching frequency and lower power consumption, upgrading of controlling method and the appearance of low-cost and high-magnetic-level permanent magnets. It not only maintains good speed control of traditional type, but also enjoys the advantages of contacting and diverting without sliding and spark, high reliability, long service life and low noise. Therefore, it is widely applied to the fields including aerospace, numerical control machines, robots, electric vehicles, computer peripherals and home appliances.
10/27/2022 at 01:25 •
The wide use of DC gear motors is well known to all. It can be divided into brushed motor, brushless motor, and other types in accordance with diverse uses and requirements. The former two kinds of motors are considerably prevailing devices which we may use. Then what on earth the differences between these two motors? We can mainly account for them from the following three aspects:
1. Scope of Application
DC brushless gear motors are often applied to those devices requiring accurate control and fast rotation, such as aero-model motor and precise instruments which demand high speed of rotation. While brushed gear motors are widely used in power equipment, including factory motors, domestic smoke extractors, etc. Even though series motor is able to rotate at high speed, it’s lifetime cannot be as ideal as brushless motor due to its easily worn-out carbon brush.
2. Life Span
Generally, the DC brushless gear motor can be used as long as several thousands of hours. Of course, a high-quality bearing contributes to a longer life span. However, it is necessary to change carbon brush when brushed motor works longer than several hundreds of hours. Otherwise, it would have easily caused damage to bearing and the motor.
Remarkably controlled by digital variable frequency, the brushless motor is easy to achieve a few rpm to ten thousand rpm. While brushed motor begins with a relatively constant speed, so it’s a little difficult for it to adjust speed. What’s about series motor? Its short life span cannot be ignored, though it also can reach 20000 rpm.
Considering concrete application fields, various requirements and respective advantages, we need make a correct decision to choose whether brushed or brushless gear motors.
10/27/2022 at 01:17 •
In terms of the structure of product itself, the DC gear motor also belongs to an ordinary DC motor. What differs lies in a newly-added gear motor in its basic structure, which explains why it is called gear motor. This article will make a brief introduction of the principle and function of the DC gear motor.
The internal gearbox, the most significant components of a DC gear motor, is used to reduce speed. Therefore, its working principles are closely related to gearbox. Firstly, it can provide a larger torque when the rotation speed is relatively low. Secondly, different proportion of rotation speed and torque stands for a different gear ratio.
A common DC gear motor is composed of two parts, namely stationary part and rotating part. When it is under operation, the former is called the fixer which contains a metal shell and a magnetic pole to generate magnetic field. The latter gets the name as rotor, whose internal structure is much complex than fixer.
Focused on energy conversion, the main purpose of the DC gear motor is to convert electrical energy into mechanical energy of rotation. As a result, it enjoys a relatively wider use in steel machinery, factory automation and other sectors, especially leaving an impressive effect on electrolysis, electroplating, electrofusion and other industrial processes.
- Due to a smaller volume, the DC gear motor will not take up too much space during installation. In common cases, the motor enjoys favorable overload capacity and competitive durability.
- It performs competitively in saving energy and converts internal energy efficiently into another. Generally speaking, the working efficiency can reach more than 95%.
- The surface of the internal gearbox will be extremely sturdy after professionally heated and the vibration frequency of the motor is very small when it woks, even leaving the noise almost ignored.
- It mainly adopts the design concepts pf systematization and modularization, which has a wide range of adaptability in the industry.Different types of DC gear motor can be arranged and combine into a variety of usage schemes, so the customers can choose the most suitable schema in line with their practical demands.
09/29/2022 at 05:38 •
The ball screw consists of a screw and nut with matching grooves and ball bearings that move between them. Its function is to convert rotary motion into linear motion or convert linear motion into rotary motion. Ball screw is the most commonly used transmission element in tool machinery and precision machinery, and has the characteristics of high precision, reversibility and high efficiency. Due to its small frictional resistance, ball screws are widely used in various industrial equipment and precision instruments.
The difference between ball screw and lead screw
The basic difference between a lead screw and a ball screw is that a ball screw uses a ball bearing to eliminate friction between the nut and the lead screw, whereas a lead screw does not.
1. Different structure
There are balls in the ball screw, and an arc profile on the screw shaft. This profile is hovering on the shaft according to a certain lift angle (lead angle). The ball is designed in the nut and rolls in the arc profile of the screw shaft, so it is rolling friction.
There are no balls in the trapezoidal screw, so the movement between the nut and the screw shaft completely relies on mechanical contact to produce sliding, which is sliding friction.
2. Different transmission efficiency
The coefficient of friction of rolling friction is much lower than that of sliding friction.
For example, both NSK and THK show that ball screw has a coefficient of friction between 0.003 and 0.01, while lead screw only has a coefficient of friction between 0.1 and 0.2.
As another example, REXROTH shows that the coefficient of friction of ball screws is between 0.005 and 0.01, while the coefficient of friction of lead screws is between 0.2 and 0.3.
This is why the transmission efficiency of most ball screws is as high as 90%, and some even reach more than 95%, while the transmission efficiency of most lead screws is less than 70%.
The transmission efficiency of the trapezoidal lead screw is low. From the perspective of energy, it is because of sliding friction, especially high-speed motion, which generates a lot of heat. If the lead screw or nut can't stand it, it will "burn". The lead screw is not suitable for high-speed operation requirements, and its maximum speed generally does not exceed 3000RPM.
The ball screw, because of rolling friction, does not generate so much heat, and the speed can reach very high, such as 10000RPM.
3. Different self-locking
The theory shows that when the lead screw transmission efficiency is greater than 50%, there is no self-locking, and when the transmission efficiency is less than 35%, there is self-locking. Therefore, the ball screw has no self-locking property, while the trapezoidal screw has a certain self-locking property.
As far as the Z direction application is concerned, the lead screw has the advantage of self-locking. Of course, in the actual situation, factors such as accuracy and speed also need to be considered.
4. Different manufacturing materials
The ball screw shaft is generally made of stainless steel or alloy steel, and the nut is generally made of copper, because copper can bear a large load, and at the same time, the friction coefficient is small, and it has a certain self-lubricating effect, just like some of our common linear bearings, or planes Skateboards, which also use copper, are exactly that reason.
The trapezoidal lead screw shaft is also made of stainless steel or alloy steel. For nuts, it is a little different from ball screws. In many cases, lead screw nuts use non-metallic materials. For example, when the load is low, synthetic engineering materials with low friction coefficient and high temperature resistance are generally used, such as nylon, race steel, PEEK, VESPEL, PET, PPS and other materials, mixed with Teflon (PTFE), to achieve low friction coefficient, At the same time, it has certain heat resistance.
5. Different applicable scenarios
The lead screw has sliding friction, and...Read more
09/29/2022 at 05:37 •
- a) External
- b) Captive
- c) Non-captive 2. Specify mounting direction
- a) Horizontally mounted
- b) Vertically mounted
- a) How much thrust needed (N) @ which speed (mm/s)?
- b) Load direction: single direction, or dual direction?
- c) Any other device pushing/pulling load besides the linear actuator? 4. Stroke
- a) How much the maximum linear velocity (mm/s)?
- b) How much the rotation speed (rpm)? 6. Screw end machining
- a) Round: what’s the diameter and length?
- b) Screw: what’s the screw size and valid length?
- c) Customization: drawing needed.
- a) No repositioning accuracy requirements, just need to ensure the motion accuracy for each single travel. What is the minimum movement (mm)?
- b) Repositioning accuracy required; how much the repositioning accuracy (mm)? What’s the minimum movement (mm)? 8. Feedback requirements
- a) Open-loop control: encoder not needed.
- b) Closed-loop control: encoder needed. 9. Handwheel
- a) High temperature and/or low temperature requirements? If yes, what’s the highest and/or lowest temperature (℃)?
- b) Corrosion proof?
- c) Dustproof and/or waterproof? If yes, what’s the IP code?
A stepper motor is an electromechanical device which converts electrical pulses into discrete mechanical movements which is called steps; it is a good choice for the application that requires accurate motion control such as angle, speed, and position, etc.
A linear actuator is a combination of stepper motor and screw, converting rotary motion into linear movement with the use of screw.
Here are some factors and key tips that need be taken into consideration when we select a proper linear actuator for a specific application
1. Determine and choose one type of linear actuator according to the application
If the linear actuator is vertically mounted, is it needed the power off self-locking function? If yes, then a magnetic brake need be equipped.
What’s the maximum distance the load to be travelled?
7. Precision requirements
If manual adjustment is needed during installation, then a handwheel need be added onto the linear actuator, otherwise the handwheel is not needed.
10. Application environment requirements
09/29/2022 at 05:36 •
Principles of Linear Stepper Motor
A linear motor is a transmission device that can directly convert electrical energy into linear motion mechanical energy without any intermediate conversion mechanism. It can be regarded as a rotating electrical machine which is cut radially and developed into a plane. The side derived from the stator is called the primary, and the side derived from the rotor is called the secondary. In practice, the primary and secondary are manufactured to different lengths to ensure that the coupling between the primary and secondary remains unchanged over the required travel range. Linear motors can be either short primary and long secondary, or long primary and short secondary. Taking into account the manufacturing cost and operating cost, short primary and long secondary are generally used at present.
The linear motor has compact structure, low power loss, high speed and high acceleration. By directly driving the load, the linear motor can realize high-precision position positioning control in different ranges from high speed to low speed.
Features of Linear Motors
First of all, the structure is simple, and there is no need to turn the linear rotation operation into an additional device for the linear rotation operation, which greatly simplifies the structure of the platform itself, and greatly reduces the weight and volume.
Second, The positioning accuracy is high. When operating in a straight line, the linear motor can be easily and directly driven, which can eliminate various positioning errors caused by the intermediate links. Therefore, the positioning accuracy is high. If the microcomputer control is used, the positioning accuracy of the entire system can also be greatly improved.
The third is fast response, high sensitivity and good follow-up. The linear motor is easy to use the magnetic suspension to support the actuator, so that there is always a certain air gap between the actuator and the stator without contact, which avoids the contact frictional resistance between the stator and the stator, and improves the sensitivity and rapidity of the system.
Fourth, the work is safe and reliable, and the service life is long. The linear motor can easily transmit force non-contact, the mechanical friction loss is not high, the failure is few, maintenance-free, so the work is safe and reliable, and the service life is long.
Fifth, high-speed, linear motor can realize high-precision position control in different ranges from high-speed to low-speed after directly driving the load.
Applications of Linear Stepper Motor
Linear stepping motors are widely used in many fields with high precision requirements, including manufacturing, precision calibration, precision fluid measurement, and precise position movement. Such as CNC plotters, recorders, CNC plotters, CNC cutting machines, disk storage, precision positioning machines, etc.
08/29/2022 at 07:29 •
Planetary reducer is a kind of deceleration transmission equipment that is widely used. It is usually used to reduce the output speed of the drive motor and increase the output torque to achieve the ideal transmission effect. It is widely used in smart home, smart communication, consumer electronics, and industrial automation. , intelligent vehicles, intelligent robots and other fields, the following describes the detailed application and characteristics of planetary reducers in various fields.
1. The field of smart home
The products in the application of planetary reducer in the field of smart home include hand-held washing machine, vacuum cleaner, refrigerator door opening and closing, rotating TV screen, baby stroller, lifting socket, sweeping robot, smart toilet, range hood lifting, TV telescopic , Lifting mosquito nets, lifting hot pot, electric sofas, lifting tables, electric curtains, smart home door locks, etc.
2. The field of intelligent communication
The products used by planetary reducer in the field of intelligent communication include communication base station ESC, base station signal electric tilt actuator, base station smart cabinet lock actuator, VR glasses ESC system, and 5G base station antenna electric adjustment actuator.
3. The field of consumer electronics
Planetary reducers are used in the field of consumer electronics in products such as mobile phone lifting camera actuators, mobile phone photo printers, smart mice, rotating speakers, smart PTZs, Bluetooth lifting headsets, electronic cigarette equipment, etc.
4. Industrial automation
The application products of planetary reducer in industrial automation include industrial valve drive system, door valve drive system, vending machine system, electric screwdriver system, intelligent logistics cabinet system, automatic reclosing, automatic feeder system, earthquake tester, bicycle lock system, etc. .
5. Smart cars
The products used by planetary reducer in smart car drives include electric car charging gun lock actuator, car logo lift and flip system, car logo lift and flip drive system, car door handle telescopic system, car tail drive system, EPB drive system, car large Light regulator systems, automotive dashboard systems, automotive electric tailgate drive systems, etc.
Planetary reducer is one of many types of reducer. The main transmission structure of the planetary reducer is composed of a planetary gear set and a drive motor. It has the characteristics of light weight, small size, large transmission ratio range, good performance, stable operation, low noise and strong adaptability, so it is widely used in micro drive field.
08/29/2022 at 07:27 •
A reduceris a machine that can change speed and output torque. The reducer is an important part of the mechanical transmission system. Now, reducers can be seen in various fields of machinery, transportation, construction, machining and other fields. So, what are the benefits of using a reducer?
1. Reduce speed, increase torque
In industrial automation applications, it is often used for precise control of low speed and high torque. In this case, a reducer is usually used. Generally In high-speed, low-torque conditions, no acceleration reducer is required.
2. Save the cost of use
The use of reducer can save the loss cost to the greatest extent! If the reducer is not used in the process of using the motor, the motor is likely to be damaged because it cannot withstand such a strong pressure when the motor is running continuously for a long time with high strength. The maintenance cost is huge, and even direct scrapping cannot accept maintenance. If a reducer is used, if damage occurs, the first one will be the reducer, and the motor will not be damaged at all, reducing unnecessary losses and achieving maximum economic benefits.
3. Effectively reduce the moment of inertia
The reducer can control the start and stop in time and change the speed. Increasing the torque through the reducer is equivalent to increasing the input power, which can reduce the power required by the input motor.
4. Can effectively save energy
Using a reducer can maximize energy savings for the user, because using a reducer can reduce the current required by the motor to meet the output torque. If you want to install the right reducer for your motor, you must choose the correct type before purchasing. There are not only a wide variety of reducers, but also different models. Types include gear reducer, worm gear reducer, planetary reducer; according to the number of transmission stages, there are single-stage and multi-stage points. Therefore, before purchasing, we must understand the characteristics of each reducer, and choose the model that can match the production needs.
08/29/2022 at 07:24 •
The gearbox is composed of gears, transmission shafts, bearings and box structures. Because the box structure is sealed, it is generally not easy to fail. The failure mainly occurs in the gears, transmission shafts and bearings. Generally, the failure of the gearbox Have:
1. Tooth error
It refers to the deviation of the gear tooth profile from the ideal tooth profile, including manufacturing errors, installation errors and errors generated in the working process. The tooth profile error is mainly manifested as plastic deformation of the tooth surface, uneven surface wear and surface fatigue.
2. Gear wear evenly
It refers to the friction damage of materials in the meshing process when the gear is used, including uniform wear of abrasive particles and uniform wear of corrosion.
3. Broken tooth
Broken teeth is a serious fault of gears, mainly in two forms: fatigue broken teeth and overloaded teeth. Generally, fatigue broken teeth are more common.
4. Shaft misalignment
Refers to the shafts at both ends of the coupling due to problems in the design, manufacture, installation or use process, the shafts are parallel but misaligned, causing the gears on the shaft to produce distributed tooth profile errors.
5. Shaft bending
When the shaft in the gearbox is slightly bent, it will cause a tooth profile error on the gears on that shaft. When the shaft is severely bent, the gearbox will generate large impact energy, causing serious consequences, which is a more serious form of failure.
6. Shaft imbalance
It refers to the unbalanced vibration of the shaft due to the existence of eccentricity, which can be caused by deformation after manufacture, installation and use. Shaft unbalance faults can cause tooth profile errors in gear drives.
7. Axial movement
When there are two helical gears engaged in meshing at the same time on the same shaft, and there is no good positioning and locking device in the axial direction, sometimes the phenomenon of axial play occurs, which is mainly caused by the unbalanced axial force. of. Axial play will seriously affect the accuracy and stability of gear transmission, and may also cause impact wear on the end face of the gear teeth.
8. Box resonance
Box resonance is a resonance phenomenon caused by the excitation of the natural frequency of the gearbox box by the impact energy. The resonance of the box body produces a large amount of shock vibration energy, which is a very serious fault and is generally caused by the outside.
9. Bearing fatigue spalling and pitting corrosion
When the shaft rotates, the inner ring and the outer ring and the rolling elements will have mechanical shock during the contact process, resulting in a force with a large fluctuation range of the shock pulse. When the rolling bearing in the gear box fails, its energy is much smaller than the vibration energy generated by the gear. , making it difficult to diagnose.
Fault diagnosis method of gearbox
Gearboxes are widely used. If there is a fault, it needs to be diagnosed in time. Generally, the reasons for gearbox failures mainly include design problems, improper operation, and faults or defects in adjacent conditions. The methods for diagnosing gearbox faults are as follows:
1. Through the dynamic signals such as vibration, noise and oil temperature generated during the operation of the gear, the signal processing method is used to complete the analysis and diagnosis of the fault.
2. According to the friction and wear theory, by analyzing the metal composition in the lubricating oil, it is judged which part of the material is, so as to judge whether it is a normal phenomenon. 3. Spectrum analysis method. When the gearbox fails, the fault information contained in the vibration signal usually appears in the form of modulation. By demodulating the fault information, you can know where the fault lies.
08/15/2022 at 02:50 •
What is a Permanent Magnet Stepper Motor?
Permanent magnet stepper motors (PM) are rotated by a magnetic rotor core through interacting with a pulsed electromagnetic field generated by the stator.
Permanent magnet step motors are generally two-phase, with small torque and volume, and the stepping angle is generally 7.5 degrees or 15 degrees. The motor has two parts: the rotor and the stator. When the stator is a coil, the rotor is a permanent magnet; or the stator is a permanent magnet, and the rotor is a coil.
How does a PM stepper motor work?
When the rotor of the motor is a permanent magnet and the current flows through the stator winding, the stator winding will generate a vector magnetic field. The magnetic field will drive the rotor to rotate by an angle, so that the direction of a pair of magnetic fields of the rotor is consistent with the direction of the magnetic field of the stator. When the stator’s magnetic field of rotates by an angle, the rotor will also rotates an angle. Each time an electrical pulse is input, the motor rotates an angle and moves forward one step. The angular displacement it outputs is proportional to the number of input pulses, and the rotational speed is proportional to the pulse frequency. If you change the coil electrifying sequence, the motor will reverse.
Therefore, the rotation of the stepper motor can be controlled by controlling the number of pulses, frequency and power-on sequence of each phase winding of the motor.
Applications of PM Stepper Motors
Permanent magnet stepping motor has the characteristics of simple structure, low noise, adjustable speed, etc.
It is widely used in bank terminals, telecommunication equipment, printers, copiers, fax machines, scanners, textile machinery, medical treatment, automatic control, building automatic control valves, etc. Besides, it is also applied in stage lighting, monitoring systems, electric advertising, electric curtains, scientific and educational equipment, air conditioning and other fields.
08/15/2022 at 02:48 •
What is an integrated stepper motor?
The integrated stepper product includes stepper motor, driver, motion controller and encoder. It integrates each unit in the stepper system into a whole, reduces the space by more than 40%, reduces the wiring by more than 50%, and has good electromagnetic Compatible features and simple system topology greatly increase the reliability and practicability of the stepping system. It is an excellent choice for customers with small installation space and high degree of system integration.
Advantages of integrated stepper motors
The integrated stepper motor has a compact structure and a small size, which can save more space. Due to the higher integration and simple wiring, it can achieve faster installation.
Since the driver and the motor are integrated, the connection between the driver and the motor is saved, the interference caused by the motor cable is effectively reduced, and the electromagnetic interference between the wires is reduced; better vibration technology and low heat generation technology are adopted, which effectively solves the problem of the motor and drive heat, vibration and noise.
Application fields of integrated stepper motors
Suitable for all kinds of small and medium automation equipment and instruments, such as: engraving machines, marking machines, cutting machines, laser imagesetters, plotters, CNC machine tools, automatic assembly equipment, etc. It works particularly well in devices where users expect low noise, low vibration, low heat generation and high speed.
08/15/2022 at 02:45 •
What is a Servo Motor?
Servo motor is a common motor that absolutely obeys the command of the control signal. Before the control signal is sent, the rotor is stationary. Once the control signal is sent, the rotor rotates immediately and instantly stops when the control signal disappears. If the motor as a controlled device, associated with servomechanism is DC motor, then it is commonly known as a DC Servo Motor. If AC operates the controlled motor, it is known as a AC Servo Motor.
Servo motor is the implementation element in the automatic control system since its obvious feature is adjustment. When there is an adjustment data signal, the servo motor runs, and the speed is proportional to the adjustment voltage. After the adjustment data signal voltage is removed, the servo motor stops running immediately.
Servo Motor Applications
Servo motors have high running accuracy and output torque accuracy, and are mainly used in equipment that requires relatively high process accuracy, processing efficiency and work reliability, such as:
1. Machinery industry: machining centers, CNC punching machines, bending machines, shearing machines, PLC program controllers, various types of automotive testing equipment, assembly equipment, and welding equipment.
2. Printing industry: drying machine, printing machine, offset printing machine, rotary machine, laser phototypesetting, proofing equipment, automatic punching machine, inkjet printer; folding machine, paper cutter, sewing machine, glue binding machine, automatic Corrugated cardboard (box) production line, automatic paper feeding and gluing machine, computer three-side bag sealing machine, shaftless high-speed offset printing machine, etc.
3. Medical industry: monitors, ultrasound machines, CT control boxes, electrocardiogram (EEG) testers, X-ray machines, slicers, hemodialysis machines, temperature controllers, etc.
4. Food industry: sterilizer, homogenizer, labeling machine, can making machine, flow controller, sealing machine, packaging machine, coffee machine, etc.
5. Rubber tire industry: steel belt production line, inner lining extrusion line, steel wire calender, double compound extruder, steel cord cutting machine, heavy internal mixer, radial tire wire machine, etc.
6. Elevator industry: door control and floor control of various elevators.