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(11) | EP 0 839 744 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Mechanism for changing a web feed from intermittent to constant motion |
| (57) A mechanism is provided for receiving a web with intermittent motion and converting
it to constant motion, particularly for severed carton items. A reciprocating carriage
has first and second adjacent idler rollers and a third roller spaced away from the
first two. A driven roller has a fixed axis and is located with respect to the third
idler roller such that the web when stung between the first and second rollers and
thence around the third roller and thence around the driven roller, assumes a quasi-boustrophedonic
configuration such that a portion of the web can be accumulated between the third
idler roller and the driven roller when the carriage moves in the direction which
increases the distance between them. Upper and lower endless belts pass partially
around the first and second translating rollers respectively and once juxtapositioned,
between the two idler rollers, thence around the third translating idler roller, thence
around the driven roller, thence along different respective return paths. The driven
roller is rotated at substantially constant speed, and the carriage is moved in a
first direction corresponding to that portion of the cycle when the web movement has
been arrested, and for moving the carriage in the second direction opposite the first
direction when web movement resumes. |