主权项 |
1. A clamp device for use on a carrier structure for supporting and transporting a canvas painting-in-progress which is affixed to a picture frame having, top, opposing side and bottom members each of which members has a front face, a rear face, an outer edge face, and an inner edge face, wherein each said rear face has a canvas tacking surface and a bare surface portion, wherein an artists canvas is stretched over said front faces, said outer edge faces and said tacking surfaces of said rear faces of said frame members with innermost edge portions of said canvas affixed to said tacking surfaces, wherein said clamp device is adapted to be removably and position adjustably affixed to at least one frame member and is comprised of substantially parallel, spaced front and rear walls held in spaced relationship by web means affixed to each wall and thus forming a channel shaped cavity into which at least one said frame member can be nested with said rear wall of said clamp device being spaced from said rear face of said one frame member and with said front wall of said clamp device being adapted to be inserted between said front face of said one frame member and overlying adjacent portions of said canvas, said clamp device further comprising a screw shaft having a rotation axis and in axial succession an inner threaded section, an intermediate section and an outer torquing section, said threaded section being threadedly mounted through said rear wall for axial movement toward and away from said bare surface portion of said rear face of said one frame member, a pair of annular shoulder means axially spaced from each other on said intermediate section and each extending radially outwardly from opposite ends of an annular journal surface portion of said intermediate section to form an annular guide follower groove for slidably receiving with close tolerances portions of an elongated, substantially upright guide rail stanchion lying adjacent to a longitudinally extending guide slot formed substantially axially in said stanchion of a painting carrier structure whereby all painted surfaces of the canvas are held in fixed position on the carrier structure and spaced from and isolated from any part of the carrier structure. |