This invention relates to winding operations, and more particularly to apparatus for loading or unloading a drum on a winding machine.
Winding and unwinding machines of the gantry type, capable of taking large-size drums, are described in Swiss Pat. No. 576,392, among others. Such large drums hold electric cable, for example, and because of their size and weight, they are difficult to load and unload. As a matter of fact, these drums may weigh several tons, and in some instances their flanges are several meters in diameter. In most cases, the drum supports are movable vertically on the uprights of the gantry, so that the trunnions can be brought to the level of the axis of the drum when it has been placed between the uprights, and the drum can thus be seized and lifted into winding or unwinding position. However, the fitting of these trunnions into the axial recesses in the flanges of the drums may be hampered if the axis of the drum is not perfectly aligned with the axis of the trunnions.
It has already been envisaged to equip winding machines of this type with special devices to facilitate the placing of the drums, which in most cases are brought up by means of a fork lift having prongs long enough so that the two flanges of the drum are balanced thereon. German Pat. No. 508,677, for example, provides for fixed, parallel support bars which automatically center the drums before they are lifted to be gripped by the trunnions of the drum supports.
Yet this prior art device does not solve all the problems which arise, and in particular, it requires excavation in the floor of the premises where the winding machine is installed, which is a drawback as regards the general layout of a cable-manufacturing plant.
It is therefore an object of this invention to provide improved drum loading and unloading apparatus which represents a simpler and more practical solution to the above-mentioned problems than prior art apparatus.
To this end, in the apparatus according to the present invention, the improvement comprises a carriage on which there are mounted two pairs of carrier elements aligned along two parallel horizontal axes so as to be able to support a drum resting with its flanges on these carrier elements, means for guiding the carriage, capable of causing it to move in a direction perpendicular to the mentioned axes, and drive means capable of moving the carriage between a disengaged position and a loading or unloading position.