Automatic web splicing system

An automatic web splicing system comprising:

• a web feed source including a pair of web rolls, an active path guiding a web drawn out from one of the web rolls to a main feed path as an active web, and a standby path where a web drawn out from the other web roll is caused to stand by as a standby web;
• a main feed roller disposed on the main feed path and feeding the active web toward a consumption device;
• residual amount-detecting means for detecting a web residual amount of said one web roll;
• a sub-feed roller disposed on the standby path, said sub-feed roller feeding the standby web from said other web roll along the standby path when the web residual amount reaches a predetermined value or less;
• speed-detecting means for detecting a feed speed of the standby web;
• and
• splicing means for splicing the standby web to the active web in a splicing position when the feed speed of the standby web matches that of the active web, simultaneously cutting the active web in a potion upstream from the splicing position while cutting the standby web in a position downstream from the splicing position, and changing over the web to be fed from the main feed roller from the active web to the standby webs;
• wherein said web feed source includes:
• a pair of spindles on which said web rolls are mounted, respectively;
• driving means for rotating said web rolls individually through said respective spindles thereof;
• a pair of buffer chambers located on the active path and the standby path, respectively, said buffer chambers being capable of sucking the webs fed along the respective paths and drawing the respective webs thereinto so as to form the respective webs into a U-shape;
• a pair of draw-detecting means for detecting amounts of the webs drawn into said buffer chambers, respectively;
• controlling means for controlling a rotational speed of each of said web rolls by means of said driving means so that the detected draw-in amount of the corresponding web is maintained within a predetermined range;
• and
• pushing means for pushing the webs toward the respective buffer chambers.