REAR WHEEL TURNING HYDRAULIC DRIVE Russian patent published in 2003 - IPC

FIELD: load-lifting facilities. SUBSTANCE: invention can be used in hydraulic drives of rear wheels of self- propelled short0base chassis load-lifting cranes. Proposed rear wheel turning hydraulic drive contains wheel turning hydraulic cylinders, supply mains with pilot controlled check valves connected with crane hydraulic system by means of electrically operating three-position hydraulic distributor, limit switch disconnecting hydraulic distributor when rear wheels are in neutral position. Hydraulic cylinder is installed in lower frame of crane and is furnished with spring-loaded two-way normally-closed valve. Plunger of two-way normally-closed valve is made for engagement with end of inner two-sided rod. Restrictor and pneumatically controlled normally open valve are installed in one of working main line of three-position hydraulic distributor. Control space of normally open valve, through restrictor is connected with normally-open electropneumatic valve, in parallel with space between plunger of two-way normally-closed valve and end of inner two-sided rod. Pressure main line of electropneumatic valve operating pilot controlled check valve, as well as pressure mainline of electropneumatic valve operating pneumatically operated normally open-valve, are connected in parallel through check valves with receiver. EFFECT: no manual control over rear axle wheel fixing process under transportation conditions owing to automation of process. 2 dwg