Abstract: Disclosed are a testing system and testing method for a magnetic refrigerator. In the system, an adjustable load includes a heating container, and a flow direction control structure. The heating container is provided with an inlet, an outlet, and a heater with controllable heating power. The flow direction control structure is configured to enable a heat exchange fluid flowing out from a cold end of any magnetic regenerator module in magnetic regenerator modules arranged in pairs to flow into a cold end of another magnetic regenerator module through the inlet and outlet of the heating container in sequence, the heater is used to heat the heat exchange fluid inside the heating container, and an on-off state between the adjustable load and the cold end of any magnetic regenerator module is controllable.

Abstract: The present invention is directed to a bi-stable coupling for controlling the depth of a tool insertion, such as drilling, and similar processes. The bi-stable coupling can be used to penetrate (e.g., drill or push) through a material layer of unknown thickness without plunging the tool into the adjacent layer. In accordance with the invention, in a first state, force is applied to the tool to initiate penetration and a reactive force maintains the device in the first state during penetration and when tool penetrates the material, the reactive force is diminished enabling the device to transition to a second state in which the tool becomes retracted. In medical applications, the invention allows for drilling through bone of unknown thickness without plunging into the adjacent soft tissue.

Abstract: A flexible water pipe, including: an inner pipe, which can extend or contract when water-filling or dewatering in the flexible water pipe; an outer pipe, which can unfold or wrinkle when water-filling or dewatering in the flexible water pipe; several rings arranged outside the inner pipe; a joint in inflow side, which is used to fasten the inner and outer pipes in inflow side; and a joint in outflow side, which is used to fasten the inner and outer pipes in outflow side; wherein, the outer pipe is arranged outside the inner pipe and the ring.

Abstract: The present invention is directed to a bi-stable coupling for controlling the depth of a tool insertion, such as drilling, and similar processes. The bi-stable coupling can be used to penetrate (e.g., drill or push) through a material layer of unknown thickness without plunging the tool into the adjacent layer. In accordance with the invention, in a first state, force is applied to the tool to initiate penetration and a reactive force maintains the device in the first state during penetration and when tool penetrates the material, the reactive force is diminished enabling the device to transition to a second state in which the tool becomes retracted. In medical applications, the invention allows for drilling through bone of unknown thickness without plunging into the adjacent soft tissue.