Rolling guide unit

A rolling guide unit assembly which comprises a first member, and a second member disposed in an opposing relation with respect to the first member, and relatively movable along the first member through a pair of rolling guide units arranged on bilateral side surfaces of said first member, said pair of rolling guide units comprising:

• guide rails respectively secured to both side surfaces of said first member;
• a movable member secured to said second member disposed so as to oppose bilateral side surfaces of said guide rails and having a pair of upper and lower support portions extending along lateral side portions thereof by which the guide rails are clamped at upper and lower side surfaces thereof;
• and
• a number of rolling members rollably disposed in rolling member rolling grooves formed in the upper and lower side surfaces of the guide rails and opposing surfaces of the upper and lower support portions of the movable member in a mutually facing manner,
• wherein each of said rolling member rolling grooves has an arcuate cross section having a curvature larger than a radius of each of the rolling members so that the rolling members are movable along the arcuate shape of the rolling member rolling grooves;
• and
• wherein said guide rails are curved and each of said upper and lower side surfaces are parallel.

A rolling guide unit comprising:

• a relatively movable member provided with a main body portion and a pair of upper and lower support portions extending from lateral end portions of the main body portion so as to provide a recessed portion between the main body portion and both the support portions, said support portions having inner surfaces in which rolling member rolling grooves are formed;
• a guide rail disposed in the recessed portion of the movable member so that upper and lower side surfaces of the guide rail face the inner surfaces of the support portions, respectively, the upper and lower side surfaces of said guide rail being formed with rolling member rolling grooves at positions corresponding to the rolling member rolling grooves of the upper and lower support portions, respectively;
• a number of rolling members disposed to be rollable between the corresponding rolling member rolling grooves of said guide rail and said upper and lower support portions of the relatively movable member so that each of the rolling members contact the rolling member rolling grooves at two contact points and the rolling members apply load to the rolling member rolling grooves associated therewith, said movable member and the guide rail being relatively movable through the rolling of the rolling members;
• a transporting element, positioned in the vertical direction with respect to relatively movable member and the guide rail mounted to one of the relatively movable member and said guide rail;
• wherein each of said rolling member rolling grooves has a cross section of arcuate shape and having a radius of curvature larger than that of the rolling members, and the contact points are displaceable along the arcuate shape of the rolling member rolling groove;
• wherein an initial contact angle formed between a line connecting the two contact points on the rolling members to the rolling member rolling grooves and a horizontal line passing through a center of the rolling member is set to substantially 90.degree.;
• and
• wherein said horizontal line is perpendicular to said vertical direction and perpendicular to a direction of movement produced by said transportation element.