| 摘要 |
A water pump (30) includes an impeller chamber (32) formed in a housing (31), a swirl chamber (40) formed in the housing (31) to communicate with a coolant passage (8) and the impeller chamber (32), and an impeller (33) that is supported to be free to rotate in the impeller chamber (32) and rotates in conjunction with an engine (2) so as to take in a coolant and discharge the coolant into the coolant passage (8) via the swirl chamber (40). The swirl chamber (40) is formed to be divided into a first swirl chamber (41) that communicates with the coolant passage (8) at all times, and a second swirl chamber (42) and a third swirl chamber (43) respectively connected to the coolant passage (8) via thermostats (S1, S2) respectively having switch valves that can be opened and closed. The thermostats (S1, S2) are operated to open and close, thereby connecting and cutting off the swirl chambers (42, 43) and the coolant passage (8), in accordance with a temperature of the coolant. |
