| 摘要 |
There is an electric fuse arrangement for a hammer-blow valve (1), in which there are located in an electrical control circuit (3) the control contact (6) of a foot switch (7), an electrical actuating device (2) of the hammer-blow valve, and a voltage source (4, 5). It is desired in this case for undesired trippings of the forging hammer to be practically avoided with the aid of simple means. This is achieved by using an additional fuse probe (12) so that a double timer (26A + 26B) is set going, which during a set time interval keeps closed a fuse contact (29), which opens after expiry of the time interval, of a first monitoring relay (17) and keeps closed a fuse contact (30) of a third monitoring relay (18) in the control circuit (3), and that the contact (11) of the fuse probe (12) is located in the input circuit (25) of the timers (26A + 26B) in series with the break contact (8) of the foot switch (7), the break contact (13) of the first monitoring relay (17), the break contact (14) of the monitoring relay (18), and the break contact (16) of a second monitoring relay (20), which is actuated in the event of an offset voltage in the control circuit (3). What is essential are the control functions and their combination with the time scanning "operationally ready". <IMAGE>
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