Web edge guide system

Claim 2

Apparatus for detecting and correcting the lateral position of a longitudinally travelling web, said apparatus comprising: first means for sensing the lateral position of said web at a first position and in response thereto for correctively laterally displacing said web, if misaligned, to a predetermined lateral position at said first position; second means for sensing the lateral position of said web at a second position, said second position being spaced apart from said first position along the longitudinal dimension of said web; and means interconnecting said first and second means for limiting the maximum corrective lateral displacement imparted to said web by said first mans to a predetermined amount.

Claim 3

The invention according to claim 1 wherein said first means comprises a movable sensing member, a sensor on said sensing member, and a pair of opposed resilient members coupled to said sensing member for biasing said sensor to a predetermined position corresponding to said predetermined lateral position of said web.

Claim 4

The invention according to claim 2 wherein said inter-connecting means comprises means for preventing movement of said sensing member to said predetermined position so long as the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of displacement.

Claim 5

The invention according to claim 3 wherein said movement preventing means includes stop members responsive to said second means, said stop members being positionable within the path of movement of said sensing member for preventing movement thereof.

Claim 6

The invention according to claim 2 wherein said inter-connecting means comprises a pair of opposed stop members, one of said stop members being positionable within the path of movement of said sensing member to prevent movement of said sensing member to its predetermined position whenever the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of lateral displacement.

Claim 7

The invention according to claim 5 wherein said inter-connecting means further comprises a pair of signal lights, each of said signal lights being responsive to movement of one of said stop members to a position wherein it prevents movement of said sensing member.

Claim 8

The invention according to claim 1 wherein said inter-connecting means comprises means for indicating whenever the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of lateral displacement.

Claim 9

The invention according to claim 7 wherein said indicating means comprises a pair of signal lights.

Claim 10

The invention according to claim 1 wherein said inter-connecting means comprises a pair of opposed stop members, said stop members being responsive to said second means for movement to a position whereby said stop members inhibit repositioning of said web to said predetermined lateral position so long as the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of lateral displacement.

Claim 11

The invention according to claim 9 wherein said first means comprises means responsive to movement of said stop members to said inhibiting position for partially repositioning said web.

Claim 12

The invention according to claim 10 wherein said first means comprises a movable sensing arm, a sensor on said arm, and a pair of opposed resilient members coupled to said arm for biasing said arm and sensor towards a predetermined position corresponding to said predetermined lateral position of said web, said stop members preventing movement of said arm to its predetermined position whenever said stop members are in said inhibiting position.

Claim 13

The invention according to claim 11 wherein said inter-connecting means further comprises a pair of signal lights, each of said signal lights being responsive to movement of one of said stop members to said inhibiting position.

Claim 14

Apparatus for detecting the lateral position of a longitudinally travelling web and for moving said web to a predetermined lateral position without exceeding a predetermined maximum amount of lateral displacement, said apparatus comprising: first and second movable sensing arms, said arms sensing the lateral position of said web at first and second positions, said sensing positions being spaced apart from each other along the longitudinal dimension of said web; a pair of opposed resilient members coupled to said first arm for biasing said first arm towards a predetermined position corresponding to said predetermined lateral position of said web; means responsive to the position of said first arm for moving said web towards said predEtermined lateral position; and a pair of opposed stop members, said stop members being responsive to the position of said web at said second position for movement to a position within the path of movement of said first arm to prevent movement of said first arm to its predetermined position whenever the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of displacement.

Claim 15

Apparatus for detecting the lateral position of a longitudinally travelling web and for moving said web to a predetermined lateral position without exceeding a predetermined maximum amount of lateral displacement, said apparatus comprising: first and second movable sensing arms, said arms sensing the lateral position of said web at first and second positions, said sensing positions being spaced apart from each other along the longitudinal dimension of said web; a pair of opposed resilient members coupled to said first arm for biasing said first arm towards a predetermined position corresponding to said predetermined lateral position of said web; means responsive to the position of said first arm for moving said web towards said predEtermined lateral position; and a pair of opposed stop members, said stop members being responsive to the position of said web at said second position for movement to a position within the path of movement of said first arm to prevent movement of said first arm to its predetermined position whenever the lateral displacement of said web between said first and second positions is at least as great as said predetermined maximum amount of displacement.

Claim 16

The invention according to claim 13 wherein said apparatus further comprises a pair of signal lights being responsive to movement of one of said stop members to its movement preventing position.