A series of novel kind of pumps and motors were designed, which were based on a new structure called by double-stator. For double-stator, one rotator corresponds two stators and more than one pump or motor can work alone or be combined just in one shell. After introduced the working principle of double-acting double-stator motor and the definition of symbols, a novel theory named multi-pump and multi-motor hydraulic transmission was proposed. The output torque in a variety of connection for double-acting multi-pump and multi-motor transmission was discussed in details. The results show that this new kind of hydraulic components can better meet the actual requirements and has broadly potential applications.

设计了基于“双定子”结构的新型泵和马达。在双定子结构中，一个转子与两个定子分别相互配合，在一个壳体内多个泵（马达）可以同步工作且相互独立。以双定子、双作用马达为例，介绍了它的工作原理;在定义了这类新元件职能符号的表示方法和双定子多泵多马达传动方式之后，以双作用定量多泵多马达传动为例，对泵和马达不同组合连接方式下马达的输出转矩进行了分析，结果表明，双定子定量马达能够输出多种不同扭矩。这种新型的双定子泵（马达）及其传动方式在行走机械、机床设备等领域有广泛的应用前景。

液压传动, 泵, 扭矩, 差动马达