Abstract A safety control mechanism for a load line forming part of an extensible boom crane which has a plurality of sections moved relative to each other by power means. The cable supports a load supporting member on one of the crane sections and is reeled or unreeled from a driven drum supported adjacent another of the sections. The safety control means incorporates mechanism which will render the power means inoperative when the tension on the cable reaches a certain level. The safety control means consists of a bracket pivotally supporting the drum and pivoted about an axis. The bracket is normally biased to a first position, with the biasing means accommodating movement from the first position after the tensile load exceeds a lower level to actuate control means, forming part of the power means, to render the power means inoperative when the tensile load on the cable exceeds a desired maximum level.
Inventors
👤 Gerald P Lamer
👤 Lembit Vaerk
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-09 05:25
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/88; B66C23/90
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
181 words
An implement comprising: a frame; a boom supported on said frame and including a plurality of boom sections; means for adjusting the angular orientation of the boom relative to a horizontal axis on the frame; power means for extending said boom sections relative to each other; load support means on one of said sections; a cable supporting said load support means; a driven reel connected to said cable and operable to move said load support means relative to said one of said sections; means mounting said reel at a fixed location relative to said boom including a bracket supporting said reel for rotation about an axis; sensing means for determining the load on said cable and including mounting means pivotally supporting said bracket for movement about said axis, spring means urging said bracket to a first position and permitting said bracket to pivot about said axis when the load on said cable reaches a predetermined level; and means responsive to pivotal movement of said bracket for rendering said power means inoperative when the load on said cable reaches said predetermined level.
Claim 2
Dependent Claim
181 words
An implement comprising: a frame; a boom supported on said frame and including a plurality of boom sections; means for adjusting the angular orientation of the boom relative to a horizontal axis on the frame; power means for extending said boom sections relative to each other; load support means on one of said sections; a cable supporting said load support means; a driven reel connected to said cable and operable to move said load support means relative to said one of said sections; means mounting said reel at a fixed location relative to said boom including a bracket supporting said reel for rotation about an axis; sensing means for determining the load on said cable and including mounting means pivotally supporting said bracket for movement about said axis, spring means urging said bracket to a first position and permitting said bracket to pivot about said axis when the load on said cable reaches a predetermined level; and means responsive to pivotal movement of said bracket for rendering said power means inoperative when the load on said cable reaches said predetermined level.
Claim 3
Dependent Claim
77 words
An implement as defined in claim 1, in which said power means includes a fluid ram, a fluid source and conduit means connecting said source to said ram and in which said means responsive to pivotal movement of said bracket includes valve means in said conduit means and mounted at a fixed location relative to said bracket, and an actuator carried by said bracket and adapted to operate said valve means upon pivotal movement of said bracket.