Range Hood Motor Manufacturers

Analysis of knowledge related to range hood motor

I. What is a range hood motor? ​

The range hood motor is the core power component of the range hood. It is like the "engine" of the range hood. It converts electrical energy into mechanical energy and drives the fan wheel to rotate at high speed, thereby generating suction, sucking the kitchen fumes and exhausting them outdoors. It is the key to the range hood to achieve the function of absorbing and exhausting fumes. The quality of its performance directly affects the fumes suction effect, noise level and service life of the range hood. ​

II. What is the working principle of the range hood motor? ​

The operation of the range hood motor is based on electromagnetic induction. Taking the AC asynchronous motor as an example, when the stator winding is connected to the AC power supply, a rotating magnetic field is generated, which cuts the rotor winding and generates an induced current in the rotor. The induced current is acted upon by the electromagnetic force in the rotating magnetic field, driving the rotor to rotate. The rotor drives the fan wheel to rotate at high speed through the transmission device, so that a negative pressure is formed inside the range hood. Under the action of the negative pressure, the fumes are sucked in, and after filtering, the purified air is discharged outdoors. The principle of DC motor is similar, but the speed and direction are controlled by adjusting the input voltage or current.

III. What are the unique types and applicable scenarios of range hood motors? ​

. Classification by drive mode​
DC brushless motor: uses electronic commutation technology, does not require brushes, and has almost no mechanical friction during operation. In the Chinese kitchen stir-fry scene, it can switch from low speed to high speed of more than 2000 rpm within 1-2 seconds, instantly forming a strong suction to lock the oil smoke, and the operating noise can be as low as 55 decibels, which is suitable for open kitchens or families with high requirements for quietness. However, its control system is complex and the cost is about 30% higher than that of ordinary motors. ​

AC shaded pole motor: simple structure, composed of stator, rotor and shaded pole coil, the magnetic field difference generated by the shaded pole coil drives the rotor to rotate. The speed of this type of motor is fixed at 1400-2800 rpm, the suction is stable but the adjustment range is narrow, which is more suitable for small kitchens with small amount of oil smoke such as daily steaming and stir-frying, and is commonly found in economical range hoods.​

.Classification by wind wheel drive method​
Single-axis single motor: The motor output shaft is directly connected to a single wind wheel, and the wind wheel diameter is usually 240-300mm. The concentricity of the motor shaft and the wind wheel must be accurately calibrated during installation, otherwise resonance noise is likely to occur. In an environment where the kitchen space is compact and the smoke pipe is short and straight, it can play an efficient role. For example, side-suction range hoods in apartment-style kitchens often use this configuration. ​

Dual-axis dual motor: Two independent motors drive the left and right wind wheels respectively, and can control the operation of one side separately. When cooking on one side of the stove, you only need to turn on the corresponding motor, which can reduce energy consumption by about 30%. Like in embedded integrated stoves, this design can accurately respond to the different oil smoke volumes on the left and right stoves to avoid energy waste. ​

IV. what is special about the operation mechanism of the range hood motor? ​

Take a brushless DC motor as an example. Its operation starts with a pulse signal sent by the controller. The signal triggers the stator winding to generate an alternating magnetic field. The permanent magnet on the rotor rotates under the action of the magnetic field force. During the rotation process, the rotor position sensor feeds back the speed information to the controller in real time. The controller adjusts the current size according to the set gear to stabilize the speed. When the oil smoke concentration suddenly increases (such as sudden stir-frying), the sensor captures the change in the wind wheel load, and the controller will increase the current within 0.5 seconds and increase the speed by 10%-20% to ensure that the oil smoke does not escape. The AC motor relies on the grid frequency to form a rotating magnetic field. The speed is limited by the grid frequency. The adjustment needs to be achieved by changing the number of winding turns, and the response speed is relatively slow. ​

V. What are the special significances of the key performance parameters of the range hood motor? ​

.Static pressure value: refers to the pressure generated by the motor when the wind wheel is completely blocked, in Pascal (Pa). When the exhaust pipe is more than 3 meters long or has more than 2 turns, the static pressure value must reach more than 300Pa to avoid oil smoke backflow. For example, in high-rise residential buildings, multiple households exhausting smoke at the same time will increase the pressure of the public flue. High static pressure motors can "break through" the resistance to discharge oil smoke. ​

. Speed ​​fluctuation rate: refers to the deviation range between the actual speed of the motor and the rated speed. The fluctuation rate of high-quality motors can be controlled within ±5%. Excessive fluctuation rate will cause the suction force to be strong and weak. For example, when stewing, if the fluctuation rate exceeds 10%, the oil smoke suction and exhaust may be discontinuous. ​

. Temperature rise limit: After the motor runs continuously for 1 hour, the difference between the surface temperature and the ambient temperature must be less than 70K (Kelvin). If the temperature rise is too high, it will accelerate the aging of the insulation material. For example, if the temperature rise of a certain motor reaches 80K, its service life may be shortened to 60% of the normal situation. ​

VI. What are the exclusive points for daily maintenance of range hood motors?​

.Bearing lubrication maintenance: Every 6 months of use, 1-2 drops of special lubricating oil (such as No. 3 lithium grease) can be dripped into the motor bearing oil filling port (some models have design) to reduce bearing wear. Before oiling, the power must be turned off, and the oil around the oil filling port must be cleaned with a cotton swab to avoid impurities. ​

.Moisture-proof treatment of windings: During the rainy season in the south, the motor can be powered on and run for 10 minutes every month to use the motor's own heat to dissipate internal moisture and prevent the winding from being damp and short-circuited. If it is not used for a long time (more than 1 month), the motor part needs to be covered with a dust cover. ​

.Wind wheel balance calibration: When the motor vibrates slightly during operation, check whether the wind wheel is sticky with oil. Wipe the wind wheel blades with a soft cloth dipped in neutral detergent to ensure that the weight on both sides is even. If necessary, ask a professional to calibrate with a balancer to avoid aggravating motor wear due to wind wheel imbalance. ​

VII. What are the progressive methods for troubleshooting range hood motors?​

.Layered troubleshooting of motor failure​
Primary troubleshooting: Check whether the range hood power switch rebounds in place, use a voltage tester to test whether the socket is powered, if the socket is not powered, check the household circuit breaker. ​
Intermediate troubleshooting: Disassemble the motor casing (power off), observe whether the winding has burnt marks, smell whether there is any odor, if there is, the winding may be burned. ​
Advanced troubleshooting: Use a multimeter to measure the motor winding resistance. Under normal circumstances, the difference in three-phase resistance should be less than 5%. If the resistance of a phase is infinite, the phase is broken. ​

.Step-by-step detection of abnormal noise​
Step 1: Disconnect the motor from the wind wheel, start the motor alone, if the noise disappears, the noise comes from the wind wheel (such as deformation, oil stains). ​
Step 2: If the motor alone still has noise, touch the motor casing with the screwdriver handle, put your ear close to the other end of the screwdriver to listen, and determine whether the noise comes from the bearing (if it is a "rustling" sound, the bearing is worn).​
Step 3: Check if the motor fixing screws are loose, tighten them one by one with a wrench, and observe whether the noise is reduced.