| 摘要 |
1,128,652. Automatic control systems. COAL INDUSTRY (PATENTS) Ltd. June 24, 1966 [June 29, 1965], No. 27517/65. Addition to 1,037,663. Heading G3R. [Also in Division E1] To prevent low frequency oscillations developing in the electrical - hydraulic, servo - control system of a mining installation as disclosed in Specification 1,037,663, the oscillations arising as a result of changes in the resistance encountered by the cutting member of the installation when operating, the system is further provided with means for deriving a further electrical signal characteristic of the oscillations and modifying the load signal of the system to reduce the oscillations. |
