Control device for agricultural tool hydraulic hoist - uses controlled non-return valve connected to hydraulic line for hydraulic lifting cylinder

摘要

The control device has a non-return valve (14) inserted in the hydraulic line for the lifting cylinder (12) with a control pressure input (19) coupled to a control pressure line (6,7). Pref., the non-return valve has a pressure space (23), an intermediate space (24) and a valve space (25) containing a spring-loaded conical valve element (20). The latter is coupled via an operating shaft (21) to a sliding valve piston (10) between the pressure space (23) and the intermediate space (24). ADVANTAGE - Relatively low-cost control device. The range of components used remains the same. Prevents sudden pressure impact arising from switch-over reaching three-point coupling and causing damage by limiting force to lifting cylinder.