| 摘要 |
<p>A rotary crushing machine has a flap(2a) alongside its rotor (10), to swing about a hinge point (22) at the top, with a piston (26) mounted behind it. The piston housing is connected by a line (28) to a hydro pneumatic accumulator (30) via an electromagnetic valve (36) This is located one side of the pump (31). When an oversize block enters the crushing chamber (19) it pushes the flap down against a spring (46) also behind the flap, and also pushes the piston back. This causes a non return valve (32) in parallel with the pump to close, and pressure rises until a switch (40) is closed to operate a device which in turn operates the valve (36) to isolate the accumulator (30) and to shut down the crusher. The weight of the block swings the flap back fully, falls through, and the spring (40) returns the flap.</p> |
