TELESCOPIC BOOM LENGTH CHECKING DEVICE Russian patent published in 1999 - IPC

FIELD: materials handling facilities; cranes with telescopic booms. SUBSTANCE: device has flexible member whose ends are secured on head and one rear end of last telescopic section of boom provided with at least one intermediate telescopic section. Flexible member running from above-indicated head encloses, successively, solid of revolution installed on fixed section of telescopic boom and solids of revolution installed, respectively, on front end of fixed section of boom and on rear and front ends of intermediate telescopic section of boom. Solid of revolution installed on fixed section of boom is mechanically coupled with linear movement pickup. In one design version, flexible member is made in form of cable two coils of which are wrapped around above indicated solid of revolution mechanically coupled with linear movement pickup. Flexible member tensioner in form of resilient spring member is installed between flexible member and head of last telescopic section of boom. EFFECT: provision of reliable and simple device giving true information concerning the length of telescopic boom featuring long reach. 3 cl, 3 dwg