Linear motion guide unit

A linear motion guide unit comprising:

• a guide rail having at least one first raceway groove extending lengthwise on each longitudinal side of the guide rail,
• a slider that fits over or conforms to the guide rail for movement relative to the guide rail, the slider being composed of carriages adjacent to each other and juxtaposed in series in a lengthwise direction, the carriages each having a second raceway groove lying in opposition to each respective first raceway groove of the guide rail to define a load-carrying race between respective opposed first raceway grooves and second raceway grooves,
• a return passage extending in parallel with each respective second raceway groove,
• an end cap secured to each opposite end of the slider and each end cap comprising at least one turnaround passage to connect the respective load-carrying races with the respective return passages, and
• a plurality of rolling elements disposed to roll through circulating circuits, each of the circulating circuits made up of respective load-carrying races, respective return passages, and respective turnaround passages;
• wherein adjacent carriages are joined together at a joint, each joint comprising two connector plates, each connector plate has an identical structure, one connector plate being fastened to each carriage defining the respective joint, each connector plate having a front surface, wherein respective front surfaces face each other at each joint, and each connector plate being provided on the front surface with a tenon or projection, and a mortise which are widthwise spaced away from each other;
• and
• wherein the adjacent carriages at each joint are joined together such that respective connector plates are in face-to-face engagement on respective front surfaces of the connector plates and the tenons fit into the mortises to provide tenon-and-mortise joints.