| 摘要 |
If a shutoff valve (24a) is opened, resulting in an accumulator (22) being connected to a high pressure liquid path (Lh), and if a sucked liquid path (Li) is connected to the high pressure liquid path (Lh) by means of a selector valve (24b), then a pump motor (M) can be operated as a motor by means of liquid accumulated in the accumulator (22). If the shutoff valve (24a) is opened, resulting in the accumulator (22) being connected to the high pressure liquid path (Lh), and if the sucked liquid path (Li) is connected to a low pressure liquid path (Ll) by means of the selector valve (24b), then the pump motor (M) can be operated as a pump, with the result that liquid in a tank (21) can be accumulated in the accumulator (22). If the shutoff valve (24a) is closed, and if the low pressure liquid path (Ll) is connected to the high pressure liquid path (Lh) by means of the selector valve (24b), then a pump motor (M) can be rotated under no load. Consequently, under a simple configuration with a small number of parts, it is possible to make changeovers among three circuits, namely, a drive circuit (for motor operation), a regeneration circuit (for pump operation), and a neutral circuit (for no-load operation). |
