In the field of hydraulic transmission, gear motor and Orbital motor are the two most commonly used low-speed power elements, widely used in engineering machinery, agricultural machinery, industrial automation and other scenarios. Although both are volumetric hydraulic motors, due to the differences in working principle, structural design and performance characteristics, they show a significant division of labor in practical applications. This article from the technical principle, in-depth analysis of the core differences between the two and the applicable scene, for engineering selection to provide reference.
1. Gear motor: Efficient transmission with simple meshing
Working Principle: Through the meshing and separation of a pair of involute gears, the volume of the closed chamber changes. When high-pressure oil enters the chamber, it pushes the gears to rotate and output torque. Typical structures include external gear motors (e.g. Rexroth GM series) and internal gear motors.
Core features: simple structure, only a few parts such as gears, bearings, shells, etc., low manufacturing cost; wide speed range (500-3000r/min), but low torque density (torque under the same displacement is 30% lower than the Orbital motor); anti-pollution ability, oil cleanliness requirements of ISO 19/16 can be stable operation.
2. Orbital motor: the advantage of low speed and heavy load of cycloid gears.
Working Principle: Adopting cycloid pinwheel meshing (the stator is multi-tooth internal gear, the rotor is less-tooth external gear), forming a number of closed cavities through the simultaneous contact of multiple teeth. High-pressure oil pushes the rotor to do planetary motion, outputting high torque. Representative models are Danfoss OMT, Eaton 2K series.
Core features: multi-tooth meshing design, high torque density (torque is 2-3 times higher than that of a gear motor under the same displacement), which can directly drive large loads; the lowest stabilized speed is as low as 15r/min, which is suitable for high-precision and low-speed control; the structure is compact, with a volume that is 40% smaller than that of a gear motor, but the internal parts are more precise.
3.In-depth analysis of application scenarios
(1) Gear motor: high-speed light load and cost-effective priority scenarios
Typical applications: ① industrial automation: conveyor belt drive (such as food packaging lines, the need for more than 1000r/min speed, torque 50-200N・m), machine tool spindle cooling pumps; ② agricultural machinery: small sprayers, feed mixers (speed 600-1500r/min, small load changes); ③ auxiliary components of the hydraulic system: steering pumps, lubrication pumps (cost sensitive, allowing some noise). (cost-sensitive, allowing a certain degree of noise).
Advantageous scene characteristics: speed needs to be higher than 500r/min, and torque ≤ 500N・m; working conditions are clean, or allow regular replacement of coarse filter element.
(2) Orbital motor: low-speed heavy-duty and complex working conditions.
Typical applications: ① engineering machinery: excavator slewing mechanism (30r/min, torque 2000N・m), loader bucket drive (need to withstand shock loads); ② agricultural machinery: combine harvester cutting table (50r/min precision speed regulation), tractor drive wheels (direct drive tires, eliminating the speed reducer); ③ mining equipment: drilling rig feeding system (low-speed, high torque, to adapt to dust, vibration environment), bazhaji travel agency Mining equipment: drilling rig feeding system (low speed and high torque, adapting to dust and vibration environment), bazhaji traveling mechanism (IP67 protection level requirement).
Advantageous scenario characteristics: speed ≤ 500r/min, and torque ≥ 300N・m; need to start and stop frequently, bear shock loads or require high-precision speed regulation; compact space, or sensitive to the weight of the equipment.
Gear motors and Orbital motors have very different application scenarios, and only by mastering the differences between the two, can you purchase the most preferred product.
orbital motors diagram
orbital motor catalog pdf
orbital motor manufacturers
orbital motor spec sheet
orbital motors for sale
hydraulic orbital motor
low speed orbital motors
orbital motor conversion chart