Description
🔧 Mitsubishi SJ-PMB04412T-B0 – Description
The SJ-PMB04412T-B0 is a Mitsubishi Electric SJ-PMB Series built-in spindle motor, designed for compact CNC machine tools requiring moderate power and high-speed spindle operation.
It is a single-coil (non dual-winding) built-in spindle motor, optimized for fast response, precision machining, and light-to-medium cutting loads.
⚙️ Key Description
- Series: SJ-PMB Built-in Spindle Motor
- Type: Built-in spindle motor (single winding, no coil changeover)
- Application: Small/medium CNC machining centers, high-speed milling & drilling
- Drive compatibility: MDS-D2-SP-200 spindle drive unit
⚡ Functional Characteristics
- Designed for balanced performance between speed and torque
- No dual coil system (simpler structure than SJ-B heavy-duty series)
- Suitable for:
- Precision machining
- Medium-load milling
- High-speed drilling and finishing operations
📊 Key Performance Overview (Factory Data)
-
Power output:
- Continuous rating: 5.5 kW
- Short-time rating: 7.5 kW (25% ED)
-
Torque (at base speed):
- Continuous: 43.8 N·m
- Short-time: 59.7 N·m
-
Speed:
- Base speed: 1200 r/min
- Maximum speed: 3000 r/min
🧩 Mechanical & Construction Details
- Rotor inertia: 0.0162 kg·m²
- Motor mass: ~14 kg (stator), ~8 kg (rotor)
- Stator outer diameter: Ø179.5 mm
- Rotor inner diameter: Ø70.6 mm
- Motor length: ~225 mm
🌡️ Cooling & Operation
- Cooling type: Liquid cooling (oil jacket required)
- Cooling flow: ~5 L/min
- Required cooling capacity: ~1200 W
🏭 Typical Applications
The SJ-PMB04412T-B0 is commonly used in:
- Compact CNC machining centers
- High-speed drilling machines
- Precision milling and finishing equipment
- Small automation systems requiring stable spindle speed
⚠️ Summary
This model sits in the mid-range PMB spindle class, characterized by:
- Moderate power (5.5 kW continuous)
- Lower torque but stable operation
- Maximum speed of 3000 rpm
- Best suited for precision and light-to-medium machining rather than heavy cutting