HS Code | Product Description | Official Doc | Tariff Rate | Origin | Destination | Effective Date |
---|---|---|---|---|---|---|
8501102000 | Electric motors and generators (excluding generating sets): Motors of an output not exceeding 37.5 W: Of under 18.65 W: Synchronous, valued not over $4 each | Doc | 61.7% | CN | US | 2025-05-12 |
8501106020 | Electric motors and generators (excluding generating sets): Motors of an output not exceeding 37.5 W: Of 18.65 W or more but not exceeding 37.5 W AC | Doc | 57.8% | CN | US | 2025-05-12 |
8543708000 | Electrical machines and apparatus, having individual functions, not specified or included elsewhere in this chapter; parts thereof: Other machines and apparatus: Other: Microwave amplifiers | Doc | 55.0% | CN | US | 2025-05-12 |
8543708800 | Electrical machines and apparatus, having individual functions, not specified or included elsewhere in this chapter; parts thereof: Other machines and apparatus: Other: Other: Electrical machines with translation or dictionary functions; video game console controllers which use infrared transmissions to operate or access the various functions and capabilities of the console | Doc | 30.0% | CN | US | 2025-05-12 |
8412298015 | Other engines and motors, and parts thereof: Hydraulic power engines and motors: Other: Other Unlimited rotary acting: Gear type | Doc | 55.0% | CN | US | 2025-05-12 |
8412298060 | Other engines and motors, and parts thereof: Hydraulic power engines and motors: Other: Other Unlimited rotary acting: Other | Doc | 55.0% | CN | US | 2025-05-12 |
8479896500 | Machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof: Other machines and mechanical appliances: Other: Electromechanical appliances with self-contained electric motor: Other | Doc | 32.8% | CN | US | 2025-05-12 |
8479891000 | Machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof: Other machines and mechanical appliances: Other: Electromechanical appliances with self-contained electric motor: Air humidifiers or dehumidifiers | Doc | 55.0% | CN | US | 2025-05-12 |
Stepper Motor
A stepper motor is an electromechanical device that converts digital pulses into discrete mechanical movements. This makes them highly suitable for precise positioning applications.
Material Composition
Stepper motors generally comprise the following key components:
- Stator: Constructed with laminated silicon steel, featuring multiple electromagnets (coils) arranged around a central core. These coils are responsible for generating the magnetic fields that drive the rotor. Copper windings are used within the coils.
- Rotor: Typically made of soft magnetic material, often laminated silicon steel or ferrite. The rotor is designed with teeth or poles that interact with the magnetic fields produced by the stator. Permanent magnets or reluctance materials can be used within the rotor, depending on the motor type.
- Bearings: Support the rotor and allow for smooth rotation. Commonly made of steel or bronze.
- Housing: Provides structural support and protection for the motor components. Usually constructed from aluminum or steel.
- Controller/Driver: Electronic circuitry responsible for sequencing the electrical pulses to the stator coils, controlling the motor's movement. Includes semiconductors like transistors and integrated circuits.
Purpose & Function
The primary purpose of a stepper motor is to provide precise, controlled, and repeatable motion. Unlike traditional DC motors that rotate continuously, stepper motors move in discrete "steps."
The function is achieved through the interaction of magnetic fields. Energizing specific stator coils creates a magnetic field that attracts or repels the rotor's poles. By sequentially energizing different coils, the rotor rotates in a defined angular increment (the step angle). The number of steps required for a full rotation determines the motor's resolution.
Usage Scenarios
Stepper motors are widely used in applications requiring accurate positioning, including:
- 3D Printers: Controlling the precise movement of the print head and build platform.
- CNC Machines: Driving the axes of milling machines, lathes, and routers.
- Robotics: Controlling joint movements and end-effector positioning.
- Printers & Scanners: Positioning the print head or scanning element.
- Disk Drives: Positioning the read/write head.
- Surveillance Cameras: Pan and tilt mechanisms.
- Industrial Automation: Conveyor systems, valve control, and automated assembly lines.
- Medical Equipment: Precise positioning in imaging devices and surgical robots.
Common Types
There are three main types of stepper motors:
- Variable Reluctance (VR): The simplest type, relying on the principle of magnetic reluctance. They have a low holding torque and require a complex driver circuit. Less common in modern applications.
- Permanent Magnet (PM): Utilize a permanent magnet rotor, providing higher holding torque and better step resolution than VR motors. They are commonly used in lower-cost applications.
- Hybrid: Combine the features of both VR and PM motors, offering the highest holding torque, step resolution, and accuracy. They are the most common type used in demanding applications.
Key Characteristics
- Step Angle: The angular displacement per pulse. Common step angles include 1.8°, 0.9°, and 7.5°.
- Holding Torque: The maximum torque the motor can sustain while stationary.
- Detent Torque: The torque required to move the motor from one detent position to another.
- Step Rate: The maximum speed at which the motor can operate without losing steps.
- Resolution: The number of steps per revolution.
- Voltage & Current Requirements: Dictated by the motor's design and application.
Stepper motors fall under the category of electric motors. Based on the provided information, several HS codes may be relevant depending on the motor's specifications.
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8501.10.20.00: This HS code covers electric motors and generators (excluding generating sets), specifically motors of an output not exceeding 37.5 W, of under 18.65 W, and synchronous, valued not over $4 each. This would apply to small, synchronous stepper motors meeting these power and value criteria.
- 85: Electrical machines and equipment, their parts; sound recording or reproducing apparatus, television-image multiplier tubes, klystrons, magnetrons and like tubes.
- 01: Electric motors and generators (excluding generating sets).
- 10: Motors of an output not exceeding 37.5 W.
- 20: Of under 18.65 W.
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8501.10.60.20: This HS code covers electric motors and generators (excluding generating sets), specifically motors of an output not exceeding 37.5 W, of 18.65 W or more but not exceeding 37.5 W AC. This would apply to stepper motors within this power range and operating on AC power.
- 85: Electrical machines and equipment, their parts; sound recording or reproducing apparatus, television-image multiplier tubes, klystrons, magnetrons and like tubes.
- 01: Electric motors and generators (excluding generating sets).
- 10: Motors of an output not exceeding 37.5 W.
- 60: Of 18.65 W or more but not exceeding 37.5 W AC.
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8479.89.65.00: This HS code covers machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof, specifically other machines and mechanical appliances, other, electromechanical appliances with self-contained electric motor, other. If the stepper motor is integrated into a larger appliance, this code may be applicable.
- 84: Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof.
- 79: Other machines and mechanical appliances.
- 89: Other machines and mechanical appliances.
- 65: Electromechanical appliances with self-contained electric motor, other.
According to the provided reference material, the HS code options related to 'stepper motor' are limited, with only the following 3 found.
Please verify the power output (under or over 18.65W, and whether it exceeds 37.5W) and the operating voltage (AC or DC) of the stepper motor to determine the most accurate HS code. If the stepper motor is part of a larger machine, consider HS code 8479.89.65.00.