US 5,311,222 A · Prism assembly

Abstract

A miniature prism assembly which in its preferred embodiment utilizes a one inch prism, a stationary target, a yoke, and a housing bracket, all in an integrated unit which can be strung with a plumb line without removing the reflective prism housing from the yoke and which can be strung in the same manner irrespective of whether the prism is adjusted for a 0 or 30 millimeter offset and while the target remains with the yoke. Further, the present invention utilizes a stationary target easily mounted and having a center line that does not alter its position irrespective of the elevation of the prism. The novel yoke and target of the present invention permit the stringing of a plumb line while the target remains affixed to the yoke by utilizing unique bushings and dual purpose slots which permit plumb line stringing around the periphery of the yoke and simultaneously assist to retain the target.

Claims11

Dependent claims

A retro-reflective prism assembly for use in conjunction with distance measurement instruments, the assembly of the type having a retro-reflective prism and a housing for retaining the prism;

the assembly comprising:
a housing bracket for retaining said housing;
a yoke;
said housing bracket being rotatably connected to said yoke for elevational tilting of said housing;
and
a generally planar target defining perpendicular center lines intersecting the center of said prism;
said target being removeably affixed to said yoke and remaining stationary relative to said housing during tilting of said housing;
said yoke having means for stringing a plumb line for ascertaining the vertical position of said housing relative to a predetermined point below the assembly, said plumb line defining a mathematical line intersecting said housing, but being strung around the periphery of said yoke.

5 more elements

Dependencies are inferred from the claim text.

Prism assembly

Life of this patent

Prism assembly

Life of this patent

Abstract

Claims11