We supply precision custom Skewed Arc Segment Magnets. They are specifically for high-performance Permanent Magnet (PM) motors and generators. As seen in our product photo, this magnet features the standard curvature of a motor arc (Convex Outer Diameter / Concave Inner Diameter). But it comes with a critical modification: the side profiles are cut at a specific Skew Angle. This “Angled” or “Parallelogram” geometry is a sophisticated engineering solution. It is used to reduce Cogging Torque (torque ripple). By skewing the magnet shape rather than the stator laminations, motor designers can achieve: – Smoother rotation, reduced vibration, and quieter operation. – But without complex stator winding adjustments. Why Skew the Magnet? 1. Eliminating “Cogging” (The Jerky Motion): The Problem: – In a standard motor, as the magnet passes the steel stator teeth, it snaps into alignment. – This causes a “step” or vibration known as cogging. The Solution: – The Skewed Edges ensure that the magnetic field enters the stator tooth gradually. – Not all at once. The Benefit: – This creates a “Soft Magnetic Transition”. – And offers silky-smooth rotation (critical for Electric Power Steering, Robotics, and high-end Audio Turntables). 2. Noise Reduction (NVH): The Function: – Smooth torque transition significantly reduces audible whine and physical vibration. The Application: – Essential for EV (Electric Vehicle) motors where cabin silence is a priority. Geometric Definitions: Defining the Skew To manufacture this part, we need a drawing that defines: 1). Radii: Outer Radius (OR) and Inner Radius (IR). 2). Thickness: Radial height. 3). Length: Axial length. 4). Skew Angle (α): The angle of the side cut relative to the axis. Note: – Are the sides parallel (Parallelogram) or Radial? Manufacturing Method: Wire EDM & Grinding Process: Standard block slicers cannot cut skewed angles easily. We utilize Wire EDM or 5-Axis Profile Grinding to create this geometry. Sharp Edges: The acute angles created by the skew are extremely sharp and fragile. We apply a controlled Edge Rounding / Tumble Finish (as seen in the photo). It prevents these corners from chipping during motor assembly. Handling & Assembly Skewed magnets are tricky to handle. Assembly Warning: Due to the “twisted” nature of the magnetic field at the skewed edges: Force: – These magnets can jump/rotate unexpectedly when brought near steel. Gluing: – We recommend using custom fixtures to hold the magnets in place on the rotor hub while the adhesive cures. – Because the magnetic centering force is different from standard arcs. Applications Electric Power Steering (EPS): Motors that must feel perfectly smooth to the driver. Servos: High-precision robotics actuators. Spindle Motors: High-speed CNC spindles. Medical Equipment: Silent motors for hospital beds or pumps. Ordering Guide: What We Need Standard text descriptions often fail for this shape. We require: 1). 2D/3D Drawing: A STEP file or PDF is mandatory to confirm the Skew Angle. 2). Motor Temperature: “What is the max operating temp?” (To determine Grade). 3). Quantity: (EDM cutting is slower than standard slicing, so lead times may vary).