Abstract: A dock leveler includes a frame, a ramp, a lip, and a linkage. The ramp is rotatably coupled to the frame for rotation between a substantially horizontal first position and an inclined second position. The lip is coupled to the ramp for rotation between a pendent position and an extended position. The linkage is coupled to the lip and includes a pivot point and a centerline. The linkage supports the lip in the extended position when the pivot point is on a first side of the centerline and allows the lip to fall pendent under the force of gravity when the pivot point is on a second side of the centerline. The pivot point is moved from the first side of the centerline to the second side of the centerline when the lip is contacted by a vehicle that creates a downward moment on the lip.

Abstract: The dock leveler of the present invention includes a frame, a ramp, a lip, and a linkage. The ramp is rotatably coupled to the frame for rotation between a substantially horizontal first position and an inclined second position. The lip is coupled to the ramp for rotation between a pendent position and an extended position. The linkage is coupled to the lip and includes a pivot point and a centerline. The linkage supports the lip in the extended position when the pivot point is on a first side of the centerline and allows the lip to fall pendent under the force of gravity when the pivot point is on a second side of the centerline. The pivot point is moved from the first side of the centerline to the second side of the centerline when the lip is contacted by a vehicle that creates a downward moment on the lip.

Abstract: A melt indexer system for determining the melt index of a plastic by testing. The melt indexer system comprises a plurality of melt indexers, each of the melt indexers including a melt chamber into which a sample of plastic to be tested is placed, a heater for melting the sample to a predetermined temperature and a test piston for extruding the melted sample through a calibrated orifice of a removable die to determine the viscosity of the sample as a function of its temperature. A robot arm and a computer programmable to control the movement of the robot arm are provided. An infeed queue holds in predetermined order a plurality of containers containing samples to be tested and a bar code reader identifies each sample to be tested. A test computer associates a particular sample with a predetermined plan for testing the sample, records and processes the melt index test results. A vacuum sipper extracts a charge of the sample from the sample container and places it in the melt chamber.