DAOLER® Friction Shims: Enabling Precision Transmission in Harmonic Drives

DAOLER® Friction Shims play a critical role in harmonic drive applications, including friction-based power transmission, preload compensation, braking anti-skid, and overload protection. Leveraging their stable coefficient of friction, high wear resistance, thermal stability, and low abrasion, these shims significantly improve positioning accuracy, backlash control, and service life of harmonic reducers. They are essential functional components in high-precision drive systems.

I. Typical Application Positions

1. Wave Generator Bearing Preload / Friction Damping
Provides consistent damping to suppress vibration and whining during high-speed operation
Compensates for bearing clearance, enhancing transmission stiffness and rotational accuracy
2. Flexspline–Circular Spline Meshing Friction Buffering
Reduces shock loads and protects flexspline tooth surfaces
Improves meshing smoothness and reduces backlash fluctuation
3. Output-End Friction Shim / Brake Friction Pair
Enables static holding and position retention
Used in fail-safe brakes for servo joints and robotic joints
4. Overload Protection Friction Clutch Assembly
Sets a constant slip torque to protect gears during overload events
Prevents impact damage to core components such as the flexspline and wave generator
5. Zero-Backlash Mechanism Friction Compensation Shim
Provides sustained axial clamping force to automatically compensate for wear

Maintains low backlash and high repeatable positioning accuracy over extended operation

II. Core Performance Advantages of DAOLER® Friction Shims

1.Stable Coefficient of Friction

Static and dynamic friction coefficients are closely matched, minimizing stick-slip vibration; precise and repeatable torque transmission.

2.Exceptional Wear Resistance & Low Abrasion

Suitable for millions of reciprocating or rotating fatigue cycles; non-shedding and does not contaminate lubrication systems.

3.Wide Operating Temperature Range

Stable operation from –40°C to 150°C; coefficient of friction remains consistent without significant thermal drift.

4.High Dimensional Precision

Thin precision shims (0.1–3 mm) with tight flatness and parallelism tolerances for harmonic drive assembly.

5.Oil Compatibility

Stable performance in gear oil and grease environments; no swelling, softening, or degradation of friction properties.

III. Performance Enhancements for Harmonic Drives

----Reduces backlash and improves positioning accuracy
----Minimizes vibration, noise, and tooth surface impact
----Extends service life of flexspline and bearings
----Enables reliable braking and safe overload protection
----Enhances repeatable positioning accuracy in robotic and servo equipment

IV. Target Applications

----Industrial robot joint harmonic drives
----Collaborative robot (cobot) and humanoid robot actuators
----Servo rotary tables and high-precision reducers
----Medical devices and precision radar positioning systems
----CNC index drives and zero-backlash transmission mechanisms