| 摘要 |
PURPOSE:To prevent unhardened material from adhering to the end surface of a piston or the like and consequently contrive to increase productivity by a method wherein the opening and closing timings of a plurality of stock liquid jetting ports are synchronized each other and at the same time the opening area ratio of one port to the other is kept nearly constant during synchronization. CONSTITUTION:A mixing head main body 21 is slidably equipped with pistons 23a and 23b, which are driven by a pair of hydraulic units 11a and 11b, for example, in the cylinder 22 of the body 21. The one piston is slidable independently to the cylinder 22 and to the other piston. A circular stock liquid jetting port 4a is closed and opened, for example, by one piston 23a and a similar jetting port 4b is closed and opened by the other piston 23b. A controlling means 20 synchronizes the opening and closing timings of the stock liquid jetting ports 4a and 4b by means of the pistons 23a and 23b. At the same time, during synchronization, the opening area ratio of the stock liquid jetting port 4a to the port 4b is kept nearly constant by controlling the hydraulic units 11a and 11b. As a result, the mixing ratio of liquid A to liquid B is kept nearly predetermined at all times. |
