ES391811A1 - Conveyor systems - Google Patents

Abstract

A power and free conveyor has a downwardly inclined section of its trolley track provided with a holding station at which is disposed a stop mechanism. The mechanism includes a stop arm which normally occupies an operative position in which it projects over the trolley track to depress into inoperative positions respective driving dogs and respective holdback dogs of trolleys on the track. In their operative positions, these driving dogs are engageable by pushers carried by an endless power chain running in a chain track spaced above the trolley track. The stop arm arrests a trolley by abutting the depressed holdback dog of the trolley. The mechanism also includes a second member which normally occupies an operative position in which it projects under the trolley track to restrain forward movement of a trolley at the holding station. On receipt of a signal from the next holding station along the track that the preceding trolley is clear of this next station, a pneumatic piston-and-cylinder device moves the stop arm into its inoperative position to cause a pusher to engage the driving dog of the detained trolley, and another such device allows the second member to move forwardly gradually into its inoperative position to cause a smooth forward movement of the trolley under the action of the pusher.