Web registry control apparatus

Claim 2

A detector for controlling the operation of a device for regulating registry of a travelling web with equipment operating thereon, said detector comprising web edge position sensing means having first and second operating zones and an intermediate nul zone, first fluid jet discharging and receiving passages disposed adjacent said first operating zone, second fluid jet discharging and receiving passages, disposed adjacent said second operating zone, and jet deflecting means disposed in said second operating zone, said jet receiving passages communicating with said device and being arranged to operate said device when either of said fluid jet receiving passages receives a jet, said first discharging passage being arranged to discharge a first jet across said first operating zone and into said first jet receiving passage in the absence of web interposed between said first passages, said second jet discharging passage being arranged to discharge a second jet into said second jet receiving passage in the presence of web in said second zone, said jet deflecting means constructed and arranged to divert said second jet from discharging into said second jet receiving passage in the absence of web in said second operating zone.

Claim 3

A detector according to claim 1 comprising structure defining spaced upper and lower detector portions and an end portion, said upper and lower portions defining a sensing gap at an edge of said web containing a nul zone, said fluid jet discharging and receiving passages being arranged to locate said first and second operating zones in said sensing gap on either side of said nul zone.

Claim 4

A detector according to claim 2 wherein said jet deflecting means comprises a third fluid jet discharging passage disposed adjacent said second operating zone, arranged to discharge a third jet across said second operating zone into said second jet to divert said second jet from discharging into said second jet receiving passage in the absence of web interposed in said second operating zone.

Claim 5

A detector according to claim 3 wherein said first jet discharging passage and said first jet receiving passage are disposed, respectively, in opposite ones of said upper and lower detector portions, and said third fluid jet discharging passage is disposed in an opposite one of said upper and lower detector portions from said second fluid jet receiving and discharging passages.

Claim 6

A detector according to claim 4 wherein said first jet receiving passage includes an inlet jet slot of cross-sectional area sufficient to receive said first fluid jet across its entire cross-sectional area, whereby portions of said first jet are prevented from deflecting off said detector portion and diverting said third jet from said second jet.

Claim 7

A detector according to claim 4 wherein said first jet discharging passage and said third jet discharging passage are located in said upper detector portion.

Claim 8

Apparatus for controlling the operation of a device for regulating the registry of a travelling web with equipment operating thereon, said apparatus comprising a sensing device responsive to the movement of said web by more than a predetermined amount in first and second directions, said sensing device being arranged to produce a first fluid stream when said web has moved more than said predetermined amount in one direction and to produce a second fluid stream when said web has moved more than said predetermined amount in said second direction, and a three position valve directly controlled by said first and second fluid streams and arranged to energize said equipment to return said web in the opposite direction from said web movement, said valve having a closed position when said web is in registry with said equipment and first and second open positions respectively corresponding to said first and second directions of web movement, said valve being actuated between said closed position and one of said first and second open positions by said first and second fluid streams, respectively, and being arranged to energize said equipment to move said web in said opposite direction from said web movement when said valve is in one of said open positions.

Claim 9

Apparatus for controlling the operation of a device for regulating the registry of a travelling web with equipment operating thereon, said apparatus comprising a sensing device responsive to the movement of said web by more than a predetermined amount in first and second directions, said sensing device being arranged to produce a first fluid stream when said web has moved more than said predetermined amount in one direction and to produce a second fluid stream when said web has moved more than said predetermined amount in said second direction, and a three position valve directly controlled by said first and second fluid streams and arranged to energize said equipment to return said web in the opposite direction from said web movement, said valve having a closed position when said web is in registry with said equipment and first and second open positions respectively corresponding to said first and second directions of web movement, said valve being actuated between said closed position and one of said first and second open positions by said first and second fluid streams, respectively, and being arranged to energize said equipment to move said web in said opposite direction from said web movement when said valve is in one of said open positions.