THK LTR Series Rotary Ball Spline with Support Bearing

The THK LTR Series is a compact, lightweight rotary ball spline with angular-contact ball raceways machined directly onto the spline nut’s outer surface to form integrated support bearings, eliminating the need for a separate bearing housing. Preloaded balls held at a 20-degree contact angle across the spline shaft’s three crests eliminate angular backlash, while the support bearing’s 30-degree contact angle (45 degrees on the more compact LTR-A variant) delivers high rigidity against moment loads. It installs easily with bolts alone, and a dedicated seal option protects the support bearings from contaminants. Three variants cover a range of needs: standard LTR (16 to 60 mm shafts), the more compact LTR-A (8 to 40 mm), and the lightweight LTR-V (16 to 25 mm).