Differences Between Two Types of Gerotor Sets in Cycloidal Hydraulic Motors: Integral vs. Pin-Type

In a hydraulic system, the cycloidal hydraulic motor plays a critical role in power transmission. At its core lies the rotor-stator set (also known as the gerotor set), which directly determines the motor’s efficiency, durability, and performance. Based on different structural designs, there are two main types of rotor-stator sets used in cycloidal motors: the integral (one-piece) type and the pin-type. Each has unique characteristics, along with its own advantages and disadvantages. Choosing the right type is essential for optimizing your system's performance.

1. Integral Rotor-Stator Set: Features, Advantages, and Disadvantages

The integral rotor-stator set is designed as a single-piece structure, usually manufactured through casting or precision machining. This integrated design reduces the number of contact points between components, enhancing the overall reliability and efficiency of the motor. With fewer frictional interfaces, this type of gerotor set helps reduce energy losses and improves power transmission efficiency.

Advantages:

• High structural stability

• Reduced internal friction

• Excellent energy efficiency

• Ideal for applications requiring smooth and consistent performance

Disadvantages:

• High maintenance cost: Since the internal parts cannot be replaced individually, any damage typically requires replacing the entire unit.

• Longer downtime during servicing

This makes it more suitable for applications where long-term performance and high efficiency are critical, and where downtime is costly.

2. Pin-Type Rotor-Stator Set: Features, Advantages, and Disadvantages

The pin-type rotor-stator set features a modular design with multiple replaceable components. This makes it easier to repair or maintain, particularly in demanding environments. Thanks to its automatic wear compensation capability, the pin-type set performs well in high-load or long-cycle operations, where durability is a priority.

Advantages:

• Easy maintenance and part replacement

• Superior wear resistance

• Self-compensating during operation

• Well-suited for harsh or heavy-duty environments

Disadvantages:

• Lower mechanical efficiency due to increased internal friction and part complexity

• May be less stable under extreme loads compared to the integral design

• Slightly more complex manufacturing and assembly processes

3. Which Cycloidal Motors Use Integral or Pin-Type Gerotor Sets?

Different cycloidal motor models utilize different gerotor set types depending on their design purpose. High-performance or premium hydraulic motors often use integral rotor-stator sets for enhanced efficiency and stability, while motors designed for rugged or maintenance-friendly applications tend to adopt pin-type sets.