Method for controlling vacuum-operated hoists and load protection device for vacuum-operated hoists

A method for operating vacuum-operated hoists comprising:

• providing at least one elastically deformable vacuum-operated lifting mechanism, configured to generate a displacement vacuum after placement on a load at the time of lifting of the load;
• providing a controllable vacuum generator;
• providing at least one motorized lifting drive;
• and
• providing a load detection device to detect weight of the load when picked up by the hoist,
• wherein the load detection device, at the time of each lifting process, after detecting that the load exceeds a predetermined tare weight of the hoist, generates a protection signal if i) the controllable vacuum generator is not turned on or ii) there is an insufficient vacuum, the protection signal performing at least one of:
• a) directly or indirectly deactivating the at least one motorized lifting drive by way of a switch-off control;
• and
• b) preventing further lifting of the load if, upon detection of the load and lift to be used, no pressure differential or an insufficient pressure differential is present, and
• wherein the load detection device automatically switches on the controllable vacuum generator to protect the load or activates the controllable vacuum generator to generate a higher pressure differential and wherein the load detection device generates a further protection signal to perform at least one operation between switching off and reversing the lifting drive when a lifted load exceeds a predefined maximum weight regardless of presence or absence of a vacuum.

A method for operating vacuum-operated hoists comprising:

• providing at least one elastically deformable vacuum-operated lifting mechanism, configured to generate a displacement vacuum after placement on a load at the time of lifting of the load;
• providing a controllable vacuum generator;
• providing at least one motorized lifting drive;
• and
• providing a load detection device to detect weight of the load when picked up by the hoist,
• wherein the load detection device, at the time of each lifting process, after detecting that the load exceeds a predetermined tare weight of the hoist, generates a protection signal if i) the controllable vacuum generator is not turned on or ii) there is an insufficient vacuum, the protection signal performing at least one of:
• a) directly or indirectly deactivating the at least one motorized lifting drive by way of a switch-off control;
• and
• b) preventing further lifting of the load if, upon detection of the load and lift to be used, no pressure differential or an insufficient pressure differential is present, and
• wherein the load detection device automatically switches on the controllable vacuum generator to protect the load or activates the controllable vacuum generator to generate a higher pressure differential, wherein actuation of the switch-off control triggers a warning signal, and wherein when a maximum weight is exceeded, a warning signal is different from the protection signal.