| 摘要 |
<p>TOP FEEDING AND EJECTING MATERIALS HANDLING DEVICE AND METHOD A materials handling device, such as a palletizer and depalletizer, has a mechanism for feeding pallets to be loaded, and ejecting pallets which have been unloaded, at the top of the device. When operated in the unloading mode, a loaded pallet is introduced into an unloading bay and placed on an elevator. The elevator is sequentially indexed upward a distance equal to each layer to be unloaded. The indexing is automatically sequenced after the last article in the layer is unloaded. Sensing devices detect when the last article has been removed. When the final, or bottom, layer on the pallet is reached, sensing devices sense the presence of the pallet and automatically index the pallet upward an additional distance so that it may be engaged by a transversely operating carriage. The elevator in the unloading bay is then moved down to the bottom of the unloading bay. When the final layer is being unloaded a second pallet is placed in position on the elevator and indexed upwardly to a ready position slightly below the pallet which is being unloaded. When the final layer has been unloaded, the carriage is operated to eject the pallet transversely out of the top of the unloading bay. The elevator is then indexed upwardly in just a few seconds to position a new pallet to be unloaded. While the second pallet is being unloaded the ejected pallet is indexed for subsequent stacking on an elevator in the storage bay of the machine. When the transverse carriage reaches the storage bay, indexing plows position the pallet on the carriage to a standard position. The carriage remains in the storage bay until the final layer on the unloading pallet is reached and the pallet has been indexed upwardly an additional distance. Then the carriage moves into the unloading bay to support the unloading pallet. The previous pallet in the storage bay is dropped onto the elevator when the carriage leaves the storage bay. The storage bay elevator is positioned a short distance below the position of the transverse carriage. When the pallet is placed on the storage elevator, the elevator is automatically indexed down a distance past a sensor and then indexed back up so that the loaded pallet is spaced a short distance below the position of the next ejected pallet. The device can be operated in the palletizing mode by reversing the above described operation. The storage bay remains the storage bay for supplying empty pallets and the unloading bay becomes the loading bay.</p> |
