SP-92 CARBON BRUSH HOLDER SPRING (RH150028) G-76
🧰 What It Is
The carbon brush holder spring is a small compression spring located inside the motor assembly of the rotary hammer. Its job is to apply consistent pressure on the carbon brush so that the brush maintains firm electrical and mechanical contact with the rotating commutator (rotor).
This part is separate from the carbon brush itself — it sits behind or above the brush within the brush holder assembly and pushes the brush forward as it wears down, ensuring reliable contact during operation.
⚙️ Technical Function
The SP‑92 brush holder spring provides:
1. Constant Contact Force
Applies continual pressure to the carbon brush so it keeps contact with the commutator surface.
Ensures stable current transfer even as the brush shortens with wear.
2. Compensates for Wear
As carbon brushes wear over time, the spring pushes the brush forward to maintain proper contact and minimize arcing.
3. Reduces Electrical Noise & Sparking
Consistent pressure helps prevent intermittent contact that causes excessive sparking and interference.
4. Supports Motor Performance
Good spring action contributes to smooth motor rotation, better torque delivery, and longer carbon brush life.