Linear stopper

1. A roller guide device comprising:

a first guide member that is provided with an arcuate guide surface, a second guide member that is provided with an arcuate guide surface which is in opposition to the arcuate guide surface of the first guide member and which has a radius of curvature larger than that of the arcuate guide surface of the first guide member, and rollers that are interposed in a freely rollable manner between the arcuate guide surface of the first guide member, and the arcuate guide surface of the second guide member, with a roller retainer having retaining holes that hold the rollers arranged in plurality in both axial and circumferential directions between the arcuate guide surface of the first guide member and the arcuate guide surface of the second guide member, wherein

each roller is provided with a central concave surface portion of which a cross sectional configuration cut by a surface passing through a roller central axis is an arcuate concave shape, and which is in contact with the arcuate guide surface of the first guide member; and end convex surface portions which continue to the axially opposite sides of the central concave surface portion, and of which a cross sectional configuration cut by a surface passing through the roller central axis is an arcuate convex shape, and which is in contact with the arcuate guide surface of the second guide member, and

a radius of a contact portion of the central concave surface portion in partial contact with the first guide member from the roller central axis, and a radius of contact portions of the opposite end convex surface portions in partial contact with the second guide member from the roller central axis are set to the same radius.

2. A roller guide device as set forth in claim 1 , wherein, assuming that an arcuate shape formed by cutting the central concave surface portion with a plane passing through the roller central axis is the central concave circular arc, a radius of curvature from a radius center of curvature of this central concave circular arc is set to be slightly larger than a radius of curvature from a radius center of curvature of the convex shaped guide surface of the first guide member and a radius center of curvature of the central concave circular arc becomes a position at a predetermined distance from the center of curvature of the convex shaped guide surface of the first guide member, so as to provide such partial contact; and

assuming that circular arcs which are formed by cutting the opposite end convex surface portions with a plane passing through the roller central axis are the opposite end convex circular arcs, a radius of curvature from a radius center of curvature of each end concave circular arc is slightly smaller than a radius of curvature from a radius center of curvature of the concave shaped guide surface of the second guide member, so as to provide such partial contact, and

the centers of curvature of the opposite end convex circular arcs are deviated or shifted by a prescribed dimension with respect to an orthogonal line which passes through the center of curvature of the guide surfaces of the second guide member, and which is orthogonal to the roller central axis.