Fastener and fastener-rod assembly

A fastener for fastening onto a rod, comprising:

• (a) an inner collar having an axial bore therethrough and a retractable spherical member projecting into the axial bore of the inner collar when the fastener is in a locked position and retracted out of the axial bore of the inner collar when the fastener is in a retracted position, the inner collar having a radially-extending bore therethrough, the radially-extending bore having an inner diameter and an outer diameter, the inner diameter being less than the outer diameter, the retractable spherical member positioned in the radially-extending bore, the diameter of the spherical member being greater than the inner diameter of the radially-extending bore, so that the spherical member projects partially through the inner diameter when the fastener is in the locked position, the inner collar having a semispherical indentation in the outside surface thereof, the semispherical indentation being radially spaced away from the retractable spherical member,
• (b) an outer collar having an axial bore therethrough, the outer collar placed uniaxially over the inner collar and having a radial hole therethrough and a ball positioned partially in the radial hole and partially extending into the semispherical indentation, the radius of the ball being smaller than the axial length of the semispherical indentation in the inner collar, the outer collar having an impression on the inside surface thereof providing a space into which the retractable spherical member may be retracted, the outer collar being slidable along the inner collar, the fastener being in a locked position when the outer collar is in its resting position relative to the inner collar in which the ball is resting in the middle of the semispherical indentation, the fastener being in a retracted position when the outer collar is moved axially out of the resting position;
• and
• (c) means for urging the ball into the axial bore of the outer collar,
• the fastener being such that it may be locked on the rod when in the locked position and removed from the rod when in the retracted position.

A fastener and rod assembly, comprising:

• (a) an inner collar having an axial bore therethrough and a retractable projection projecting into the axial bore of the inner collar when the fastener is in a locked position and retracted out of the axial bore of the inner collar when the fastener is in a retracted position, the inner collar having a tapered indentation in the outside surface thereof, wherein the tapered indentation is radially spaced away from the retractable projection;
• (b) an outer collar having an axial bore therethrough, the outer collar placed uniaxially over the inner collar and having a movable protuberance extending into the axial bore of the outer collar, the movable protuberance being shorter axially than the tapered indentation in the inner collar and being positioned in the tapered indentation, the outer collar being slidable along the inner collar, the fastener being in a locked position when the outer collar is in its resting position relative to the inner collar in which the movable protuberance is resting in the deepest portion of the tapered indentation, the fastener being in a retracted position when the outer collar is moved axially out of the resting position, and wherein the movable protuberance and the retractable projection are positioned radially in line when the fastener is in the locked position;
• (c) means for urging the movable protuberance into the axial bore of the outer collar;
• the fastener being such that it may be locked on the rod when in the locked position and removed from the rod when in the retracted position, and
• (d) a rod having an annular groove on the outside surface thereof so that the fastener is lockable on the rod,
• the retractable projection and the annular groove being sized so that the retractable projection fits into the annular groove, thereby locking the fastener on the rod.