BMS Series Cycloidal Motor
The BMS series is a range of cycloidal hydraulic motors based on a shaft-distribution structure, with the core models classified as high-performance Hydraulic orbit motors. Through modular displacement design, the series provides reliable rotary drive force for various hydraulic systems under medium and high-pressure conditions, and is commonly used in travel and work functions requiring a compact structure, low-speed stability, and high torque output.
Operating Principle
As a typical Hydraulic orbit motor, the BMS motor utilizes the stator and cycloidal rotor to form continuously changing sealed chambers. Pressure oil from the hydraulic system is distributed to these chambers in sequence by the shaft-distribution mechanism, causing the rotor to roll planetarily within the stator. The resulting orbital motion is converted by a drive link into uniform rotation of the output shaft. Because the oil chambers are filled and drained sequentially with overlapping operation, even at extremely low speeds, the drive end of the entire hydraulic system can maintain smooth torque output with minimal pulsation.
Main Performance Parameters
The BMS series Hydraulic orbit motors cover a wide displacement range, facilitating adaptation to hydraulic systems with different flow rates and pressures.
· Displacement specifications: Commonly available in multiple sizes from 50 mL/rev to 500 mL/rev, selectable as needed.
· Rated pressure: Continuous pressure approximately 14–20 MPa, with higher peak values, meeting the load requirements of medium and high-pressure hydraulic systems.
· Speed capability: Rated speed ranges from 10–200 rpm; stable low-speed operation can be achieved from 5 rpm onward, fully utilizing the low-speed, high-torque characteristics of the Hydraulic orbit motor.
· Output torque: Jointly determined by displacement and pressure differential, covering tens to over a thousand N·m, suitable for various drive tasks.
Structural Features
· Compact and high power density: By integrating the distribution mechanism and the rotor-stator pair within a single housing, this Hydraulic orbit motor can deliver high torque with low dead weight, making it suitable for integration into mobile hydraulic systems with tight space constraints.
· Contamination and wear resistance: The shaft-distribution surfaces feature an automatic gap compensation function, and both the stator and rotor are hardened, helping to maintain volumetric efficiency and enhance the reliability of the entire hydraulic system.
· Flexible combination: The standard flange and shaft extension allow multiple BMS Hydraulic orbit motors to be used in series or parallel within the same hydraulic system, simplifying circuit design.
Typical Applications
The BMS series Hydraulic orbit motors are widely used in mobile machinery and industrial equipment powered by hydraulic systems, for example:
· Construction equipment: auxiliary drive for skid-steer loaders, auger drill rotation, sweeper side brushes
· Agricultural machinery: seeder metering, combine harvester reel, fertilizer auger
· Fishery and forestry: net haulers, winches, debarking drums
· Material handling: belt conveyor auxiliary drive, mixing devices
Integration Considerations in the hydraulic system
To ensure that the BMS Hydraulic orbit motor operates efficiently within the entire hydraulic system, the displacement should be matched according to the actual torque and speed during selection, and the back pressure should be controlled through reasonable return line sizing. When driving inertial loads or vertical lifting devices, it is recommended to add a counterbalance valve or a dual crossover relief valve in the hydraulic system circuit to protect the motor and the system from shocks.
1. Core Connection Between BMS and Hydraulic Systems
The Battery Management System (BMS) is a critical technology in electric vehicles (EVs), energy storage systems, and other applications. It monitors battery status (e.g., voltage, current, temperature), estimates the State of Charge (SOC), manages charging/discharging processes, and balances battery performance to extend lifespan and ensure safety. While BMS has no direct link to hydraulic systems,in electrified hydraulic equipment (e.g., electric excavators, forklifts), BMS indirectly enhances hydraulic system stability and efficiency by optimizing battery performance. For example:
• Energy Allocation Optimization: BMS dynamically adjusts battery power output based on hydraulic system load demands, preventing overcharging/discharging and ensuring Hydraulic Orbit Motors operate in high-efficiency zones.
• Thermal Management Synergy: Hydraulic systems generate heat during operation. BMS monitors battery temperature and collaborates with the hydraulic system’s cooling module to prevent battery thermal runaway while maintaining stable hydraulic oil temperatures.
2. Technical Characteristics of Hydraulic Orbit Motors
Hydraulic Orbit Motors, particularlycycloidal rotary motors, are low-speed, high-torque hydraulic motors that align seamlessly with hydraulic system requirements:
• Structural Advantages:
• Utilize cycloidal gear meshing principles to form sealed chambers, driving rotor revolution via an eccentric shaft for low-speed, high-torque output (displacement range: 50–1250 mL/r).
• Compact and lightweight (high power density), ideal for space-constrained hydraulic systems (e.g., end effectors in agricultural/construction machinery).
• Performance Advantages:
• Low Starting Pressure: Mechanical efficiency exceeds 85%, enabling stable torque output at low speeds and reducing energy loss.
• Bidirectional Rotation: Supports forward/reverse switching, suitable for hydraulic systems requiring frequent directional changes (e.g., crane slewing mechanisms).
• High Backpressure Tolerance: Some models withstand system pressures up to 30 MPa, adapting to high-load applications (e.g., mining machinery crusher drives).
3. Synergistic Application of BMS and Hydraulic Orbit Motors in Hydraulic Systems
In electrified hydraulic equipment, BMS and Hydraulic Orbit Motors collaborate through the hydraulic system to achieve closed-loop optimization:
• Electrified Hydraulic System Architecture:
• Power Source: Battery pack (managed by BMS) supplies electricity to drive an electric pump, generating high-pressure oil.
• Actuator: Hydraulic Orbit Motor converts hydraulic energy into mechanical energy to drive loads (e.g., excavator bucket arms, robotic joints).
• Control Unit: BMS communicates with the hydraulic system controller (e.g., PLC) to adjust battery power output based on load demands, optimizing motor speed and torque.
• Collaborative Optimization Examples:
• Energy-Saving Mode: BMS monitors SOC and reduces hydraulic pump flow at low battery levels, enabling the Hydraulic Orbit Motor to operate at low speeds and extend equipment runtime.
• Dynamic Response: When rapid hydraulic system startup is required, BMS pre-charges the battery to deliver instant high power, preventing motor startup delays.
• Fault Protection: If BMS detects battery overheating or overvoltage, it triggers the hydraulic system to reduce load, preventing motor damage from abnormal oil supply.
