| 摘要 |
An improved control system for selectively clamping a die to a power press or similar machine by means of a plurality of hydraulically actuated clamps. Such hydraulically actuated clamps are provided for securing the opposed halves of the die to the bolster and ram of the press. The clamps are connected in alternating fashion to first and second fluid conduits for both the bolster and the the ram. Each of the conduits is connected to a source of pressurized fluid. The first and second conduits on the bolster and the ram provide a safety redundancy feature in case one of the conduits on the bolster or the ram fails. Each of the conduits is provided with first and second pressure sensors. The first pressure sensors are each adapted to generate an electrical output signal when the pressure in the associated conduit falls below a first predetermined level. The second pressure sensors are each adapted to generate an electrical output signal when the pressure in the associated conduit falls below a second predetermined level, the second predetermined pressure level being less than the first predetermined pressure level. A microprocessor monitors the output signals from each of the pressure sensors and regulates the operation of the source of pressurized fluid, as well as the operation of the press itself, in response thereto. A snugging feature is included in the control system for causing the ram clamps to loosely engage one of the opposed die halves during the initial setup of the press. In this manner, the die halves can be positioned precisely relative to one another before beginning normal operation of the press. |
