| 摘要 |
A percussion mole for inserting a ground-loop for a geothermal heat-pump apparatus. The ground-loop includes a first pipe and a second pipe. The mole comprises: a percussive drive mechanism; a first passage connectable to the first pipe, for receiving a driving fluid via the first pipe and delivering it to the drive mechanism, during insertion of the ground-loop; a second passage connectable to the second pipe, for exhausting the driving fluid from the drive mechanism via the second pipe, during insertion of the ground-loop; and a connection connecting the first passage with the second passage. The connection includes a non-return valve arranged to restrict flow of the driving fluid from the first passage to the second passage during insertion of the ground-loop but permit flow in the opposite direction, whereby after insertion, when the heat pump apparatus is in use, the ground-loop comprises the first and second pipes; the first and second passages; and the connection. |
