Abstract: A pneumatic-electromagnetic latch is disclosed as applied to bring the sealing jaws of an L-sealer into pressure engagement without impact. An electromagnet mounted on a piston rod of a pneumatic actuator attracts and retains an armature attached to the sealing jaws when the jaws are brought close to the sealing bed. The cylinder of the actuator is attached to the frame and when actuated it draws the sealing jaws into smooth pressure contact with the sealing bed. Upon deenergization of the electromagnet the jaws are released to open for the next sealing cycle and the release of fluid pressure in the actuator extends the piston rod to position for the next operation.

Abstract: Apparatus for loading rolls of sheet material wound on cores into automatic wrapping machines wherein spindles are employed to support the rolls on overhead bearings for unwinding comprising a support upon which one end of the roll of sheet material to be loaded onto the bearings can be lifted and slid thereonto below the bearings, a hinge support mounting one of the bearings so that it can be moved from its operative position in alignment with the other bearing to an out-of-the-way position, and whereupon the ends of the roll spindle are centered over the bearings and the lift is retracted to lower the roll onto the aligned bearings.

Abstract: An automatic high-speed wrapping machine for wrapping packages in heat sealable thermoplastic film is disclosed wherein the film seal at the side and ends of the packages is made at a high rate of speed as the packages travel through the machine. The packages travel continuously in a straight line through the machine and are delivered at the input end of the machine by a flighted infeed conveyor into a film inverting head where the packages are surrounded by the film, thence to the side sealing mechanism which forms a seal while severing the selvage from the packages, then into an end sealing mechanism where both ends of the packages are sealed and the film web connecting succeeding packages is severed. The machine produces packages which have a sealed film wrap around the entire package which is then in condition for subsequent shrinking of the film if desired to provide a package having a tight film overwrap.

Abstract: An automatic L-sealer is arranged to pass product, including fragile items and loose piles of stacked paper, tiles or similar flat articles, through the machine without abrupt drops or changes in support level for the product to avoid breakage or upsetting of the pile. In the case of stacked loose flat articles an infeed conveyor deposits a package on an air table and an insertion arm progresses the package through the overwrap station to a sealing area where the L-seal completes and separates the overwrapped package. The sealing area includes a discharge conveyor pivoted at its discharge end and elevated at the end adjacent the air table to transfer the overwrapped package without an abrupt drop but is thereafter lowered during the sealing cycle to permit the seals to be made midway of the height of the package. The insertion arm retracts out of the path of package flow during its return stroke permitting infeeding of the next package to be initiated prior to the completion of the return stroke.