Abstract A grade level comprising a hollow, fluid-tight cylindrical housing having its central axis normally disposed in a horizontal attitude. The housing comprises an annular wall portion and spaced-apart end members mounted on opposite sides thereof. A horizontally disposed shaft is mounted in the housing and extends between the end members and has a float-weight mechanism operatively rotatively mounted thereon. The mechanism comprises a float portion which extends upwardly from the shaft and a counterbalacing weight which extends downwardly from the shaft. A pair of baffles are secured to the annular wall portion at opposite sides thereof and extend substantially horizontally inwardly therefrom towards the shaft. A fluid is provided within the housing to dampen the movement of the mechanism as the housing is moved to various attitudes. A ballast material is provided in the weight portion to cause the mechanism to normally be positioned in an upright positive relative to horizontal. A sensing apparatus is provided on the housing adjacent the upper end of the float portion for sensing the movement of the mechanism relative to the housing. A read-out mechanism is operatively connected to the sensing apparatus to enable the operator to determine the grade.
Inventors
👤 Phillip A. Bane
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-02 10:48
CPC Classifications
G; G01; G01C; G01C9/00; G01C9/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
206 words
A grade level comprising, a hollow, fluid-tight cylindrical housing having its central axis disposed in a horizontal attitude, said housing comprising an annular wall portion and end members mounted on opposite sides of said wall portion, a horizontally disposed shaft centrally mounted in said housing and extending between said end members, a float-weight combination operatively rotatably mounted on said shaft, a fluid in said housing substantially filling the interior thereof, said float-weight having a width substantially equal to the distance between said end members, means for causing said float-weight to normally be positioned in an upright position relative to the shaft axis, sensing means for sensing the position of said float-weight relative to said housing, and visual read-out means operatively connected to said sensing means for indicating the attitude of said housing and support means relative to horizitonal, said float-weight comprising a float portion extending upwardly from said shaft and a couterbalancing weight extending downwardly from said shaft, said sensing means comprising a cam surface on the upper end of said float portion, a linear variable differential transformer on the upper end of said housing and having a core in engagement with said cam surface, and electrical circuit means connecting said transformer to said read-out means.
Claim 2
Dependent Claim
206 words
A grade level comprising, a hollow, fluid-tight cylindrical housing having its central axis disposed in a horizontal attitude, said housing comprising an annular wall portion and end members mounted on opposite sides of said wall portion, a horizontally disposed shaft centrally mounted in said housing and extending between said end members, a float-weight combination operatively rotatably mounted on said shaft, a fluid in said housing substantially filling the interior thereof, said float-weight having a width substantially equal to the distance between said end members, means for causing said float-weight to normally be positioned in an upright position relative to the shaft axis, sensing means for sensing the position of said float-weight relative to said housing, and visual read-out means operatively connected to said sensing means for indicating the attitude of said housing and support means relative to horizitonal, said float-weight comprising a float portion extending upwardly from said shaft and a couterbalancing weight extending downwardly from said shaft, said sensing means comprising a cam surface on the upper end of said float portion, a linear variable differential transformer on the upper end of said housing and having a core in engagement with said cam surface, and electrical circuit means connecting said transformer to said read-out means.