Lifting and stacking loads of porous material e.g. paper rolls - b applying vacuum force only slightly over wt. to be lifted until bottom of load is ventilated then increasing to at least 1.5 times higher

摘要

For lifting and transporting of loads, which will let air through, such as rolls of paper, a vacuum pad is applied. A vacuum pad (1) is placed on the load. The load is lifted by a small amount when a certain min. vacuum is applied. When the load is lifted, air is able to flow underneath the load. The load is lifted higher by applying a second higher vacuum that exerts a force which is at least fifty per cent more than the weight of the load. A pressure sensor can be used to ascertain the vacuum pressure on the section surface of the pad. A computer stores the wt. of the load or a corresp. value and controls a signal generator. ADVANTAGE - Prevents more than one load being lifted by vacuum pad which could lead to fall-off damage or injury to operators.