| 摘要 |
A handheld device for finding the angle of a slope of a surface or verifying whether a surface is level or perpendicular which has a housing with a generally planer configuration, two perpendicularly intersecting straight edges, an arcuate slot of at least 120° up to 180° having a concave and a convex side positioned in said housing said concave side facing and opposed to a long axis of the device, a sealed tubular member filed with liquid and having one gas bubble therein, position along the arcuate slot and visible on at least one side of said housing. The tubular member and a plurality of indicia along said housing adjacent to said slot, indicating degrees between 120° up to 180°. |
| 主权项 |
1. A device comprising a housing having planer configuration, two perpendicularly intersecting straight edges,
an arcuate slot of at least 120° up to 180° having a concave and a convex side positioned in said housing and opposed to a long axis of the device, said concave side facing said long axis, a sealed tubular member filed with liquid and having one gas bubble therein, position along said arcuate slot and visible on at least one side of said housing, said tubular member being calibrated to determine degree points which are marked on the housing and a plurality of indicia along said housing adjacent to said arcuate slot and said tubular member, indicating degrees along the arcuate tubular member. |
