THK has rolled out a compact ball spline family built around revised ball circulation paths, with the LTR-V rotary variant shedding up to 46% of its predecessor mass. [S1]
Specifying engineers dealing with space-constrained machine cores, energy budgets, and cycle time pressure now have a direct line into a slimmer spline nut OD and a rotary spline with markedly lower inertia. The redesign is anchored in named test conditions, so claims of high-speed durability and reduced sliding resistance variation can be checked against the published setup rather than a generic brochure. The lineup also broadens the flange choices and adds an auto-lubrication option that changes how maintenance intervals are planned. [S1]
What was released
THK has introduced a compact ball spline family aimed at lighter and more space-efficient machine cores. The named releases are Model LT-X, Model LF-X, and Rotary Ball Spline Model LTR-V, with the article also identifying Model LFK-X and Model LFH-X as additional options in the same compact series. [S1]
The article frames the release against rising labor and material costs, limited production floor space, and energy and sustainability goals, and positions a smaller, lighter machine core as the way to address all three. The three main product images show Model LF-X and Model LT-X together, and Model LTR-V separately. [S1]
The numbers and test setup as published
The compact ball splines are described as up to 20% more compact in spline nut outer diameter than conventional models, achieved through a revised ball circulation path. Rotary Ball Spline Model LTR-V is described as up to 46% lighter than its predecessors, with that gain linked to its use of the Model LT-X for the ball spline component. [S1]
The high-speed durability test used Model LT20X at a speed of 2 m/s, acceleration and deceleration of 40 m/s squared, a stroke of 650 mm, horizontal orientation, and AFB-LF Grease as the lubricant, with the article stating the test ran 10,000 km without abnormalities. A separate sliding resistance test was performed at 10 mm/s with the same grease and horizontal orientation, with the article stating the new models show smoother motion and less variation in sliding resistance than previous models. [S1]
What it means for ball spline selection
For equipment where a smaller spline nut OD is the binding constraint, the LT-X and LF-X directly address envelope reduction without abandoning the ball spline form factor. For rotational axes that benefit from a low moment of inertia, the LTR-V combines an integrated support bearing with the LT-X spline to cut mass and support rapid start and stop profiles that improve cycle time. [S1]
The LFK-X and LFH-X extend the lineup with lower core heights than the LF-X, using a square flange and a cut flange respectively, both described as lighter than the round-flange LF-X. The optional QZ Lubricator attaches to both ends of the ball spline and feeds lubricant to the raceway groove, which the article states significantly extends the lubrication maintenance interval and is positioned as an eco-conscious system that avoids contaminating the surrounding area. A cited case study describes a robot manufacturer adopting Model LF-X for an arm slide mechanism and reporting a 20% weight reduction. [S1]
How to verify the primary source
The article publishes a full table of high-speed durability test conditions and a separate table for the sliding resistance test, so the test parameters can be compared directly to the values quoted above. It also references companion articles on ball spline basics and on customization of ball splines. [S1]
Before specifying, check the THK product page at the source URL for the current catalog dimensions, load and moment ratings, the exact baseline used for the 20% OD and 46% mass claims, the published core height values for LFK-X and LFH-X against LF-X, and the QZ Lubricator fitment and maintenance interval data for the chosen shaft size. [S1]
Primary notice: Industry news.
Product encyclopedia: Ball Spline.