| 摘要 |
PURPOSE:To contrive the reduction in the generation ratio of an inferior product and the enhancement in the reliability of a printing machine, by detecting the minute change of a screen frame generated when a screen was ruptured and stopping a drive mechanism. CONSTITUTION:A sensor locating member 9 freely contacting with a screen frame being an object to be detected is fixedly provided to the leading end part of the piston rod 8 of a locating cylinder 7. A sensor 4 capable of detecting the change of the screen frame 2 in an amount of + or -0.01mm is received in and fixedly provided to the leading end of the sensor support lever 22, which is constituted so as to be connected to the main body 7a of the locating cylinder 7 through a connection plate 29, in the advance direction of said lever 22. When the leading end part of the locating member 9 is contacted with the screen frame 2, a predetermined amount (e) is held between the end surface 2a of the screen frame 2 and the leading end of the sensor 4 and the sensor 4 is set so as to hold a predetermined detection distance from the screen frame 2. The sensor 4 detects the change (e.g., deflection of about 0.01-0.6mm) of the screen frame 2 at the time of the damage of the screen to entirely stop a drive mechanism. |
