| 摘要 |
PCT No. PCT/SE91/00549 Sec. 371 Date Mar. 22, 1993 Sec. 102(e) Date Mar. 22, 1993 PCT Filed Aug. 21, 1991 PCT Pub. No. WO92/03269 PCT Pub. Date Mar. 5, 1992.A device for processing a concrete layer by water jets, comprising a jet tube on a carriage moveable to and fro along a guide. The jet tube is pivoted in planes substantially parallel to the guide and oscillates in planes making an angle with the guide. The jet tube is inclined in one direction along the extension of the guide during the movement of the carriage along the guide, and a control unit ensures that pivoting of the jet tube with an angular velocity leading to movement of a nozzle of the jet tube along the guide with a velocity substantially equal to the velocity of the carriage is initiated at the same time as the carriage is stopped in an end position, and the control unit starts the movement of the carriage in an opposite direction when the jet tube has finished its pivoting movement. |
