More than half the barbecue grills used today are powered by propane fuel contained in refillable propane tanks. The tanks are constructed according to industry standards and typically are painted and bear operating and instruction labels adhesively applied to the tank. Because barbecue grills usually are kept out of doors, over time the propane fuel tanks become soiled with cooking grease, scratched, rusted, and weathered. With increasing popularity of gas grilling, to alleviate inconvenience to the user in refilling the tanks, exchange centers have been established that will exchange empty propane gas tanks for filled and reconditioned tanks.
The exchange center will recondition the old tank as necessary for reuse. Reconditioning may involve washing the tank to remove grease and dirt, grinding or blasting the tank with metal shot to remove rust, removing old labels, repainting the tank, and applying new labels. The reconditioning process can be tedious, time consuming, and costly. Complete removal of the old labels, for example, can be difficult because adhesives employed are designed to permanently secure the label under all weather conditions. Moreover, because the exchange centers commonly are operated by small proprietors without sophisticated reconditioning and painting systems, unsightly blemishes in exposed surfaces of the tanks may remain after repainting. Hence, even when the tanks have been reconditioned, they may not have a consistent, professionally finished appearance.
A further problem with such propane storage tanks is that after initial use of a refilled tank, the user often has difficulty knowing the amount of fuel remaining in the tank. It is not an uncommon occurrence during summer holidays, when outdoor barbecuing is most frequently carried out and refill centers are closed, that fuel in the tank becomes unexpectedly extinguished.
USPTO Backgrounds
USPTO Backgrounds