Web tracking system

Claim 2

A steering roll for a continuous web, comprising: a roll having an elastomeric material as its outer perimetric surface; partition means dividing the interior of the roll into a pair of axially spaced chambers, said elastomeric material defining a wall of each of said spaced chambers; and first and second inlet means for applying fluid pressure to the interior of each of the pair of chambers to change the relative pressures applied to the axial ends of said elastomeric material to thereby effect tilting of the outer perimetric surface of said wall by relative expansion and contraction between the axial ends of said elastomeric material.

Claim 3

The steering roll as defined in claim 1 wherein said roll comprises: an axial shaft; two parallel circular end walls connected to the ends of said shaft; an intermediate circular wall connected to the shaft in a plane parallel to said end walls defining said partition means; a cylindrical sleeve of elastomeric material fitted over the outer peripheries of said end walls and said intermediate wall defining the elastomeric outer perimetric surface, one end wall, said intermediate wall and said cylindrical sleeve defining a first chamber, the second end wall, said intermediate wall and said cylindrical sleeve defining a second chamber; and a pair of stems aligned with said shaft connected to each of said end walls for rotatably supporting said roll.

Claim 4

The steering roll as defined in claim 2 wherein said first inlet means comprises: a first bore extending through said one stem, said one end wall and a portion of said shaft within said first chamber and a second intersecting bore in said shaft opening into said first chamber; and said second inlet means comprises a third bore extending through said second stem, said second end wall and a portion of said shaft within said second chamber and a fourth intersecting bore opening into said second chamber.

Claim 5

In combination with a continuous web, supporting means supporting said web for movement along a continuous path, said supporting means including a steering roll for inducing inward and outward edgewise travel of said web, said steering roll having an elastomeric material as its outer perimetric surface; partition means dividing the interior of the roll into first and second axially spaced chambers, and means responsive to inward and outward edgewise travel of said web from a predetermined alignment for applying fluid pressure to each of the first and second chambers to change the relative pressure between the chambers, to produce relative expansion and contraction between the axial ends of said elastomeric material to effect back and forth tilting of the perimetric surface of the roll between oppositely inclined positions and thereby provide the inward and outward edgewise travel of said web to maintain the predetermined alignment.

Claim 6

In combination with a continuous web, supporting means supporting said web for movement along a continuous path, said supporting means including a steering roll for inducing inward and outward edgewise travel of said web, said steering roll having an elastomeric material as its outer perimetric surface; partition means dividing the interior of the roll into first and second axially spaced chambers, and means responsive to inward and outward edgewise travel of said web from a predetermined alignment for applying fluid pressure to each of the first and second chambers to change the relative pressure between the chambers, to produce relative expansion and contraction between the axial ends of said elastomeric material to effect back and forth tilting of the perimetric surface of the roll between oppositely inclined positions and thereby provide the inward and outward edgewise travel of said web to maintain the predetermined alignment.

Claim 7

The combination as defined in claim 4 wherein the steering roll is resiliently mounted to permit tilting of the steering roll in response to changes in the relative pressure between said chambers.

Claim 8

The combination as defined in claim 4 wherein said means for applyiNg fluid pressure to each of the pair of chambers to change the relative pressure between the pair of chambers comprises: a sensing means including a receiver for receiving a stream of fluid and a nozzle aligned with the receiver for directing a stream of fluid toward said receiver, said nozzle and receiver being positioned at one edge of the web at opposite surfaces thereof for back and forth movement of said one edge of the web between the nozzle and the receiver to increase and decrease the fluid pressure received by said receiver from said nozzle in response to uncovering and covering, respectively, of said receiver; and control means responsive to increases and decreases in pressure in said receiver, said control means increasing the fluid pressure in the first chamber with respect to the second chamber to tilt the perimetric surface of the roll to one of said oppositely inclined positions which causes movement of the web in a direction to cover said receiver, said control means in response to a decrease in pressure in said receiver increasing the fluid pressure in the second chamber with respect to the first chamber to tilt the perimetric surface of the roll to the other of said oppositely inclined positions which causes movement of the web in a direction to uncover said receiver.

Claim 9

The combination as defined in claim 6 wherein the control means includes a source of air pressure, first conduit means connecting the source of air pressure to said nozzle; fluid amplification means; including first and second fluid amplifiers; first conduit means for connecting the source of air pressure to a supply port and a first control port of the first fluid amplifier and to a supply port of the second fluid amplifier; second conduit means connecting the receiver to a second control port of the first fluid amplifier; third conduit means connecting a first outlet port of the first fluid amplifier to a first control port of the second fluid amplifier; fourth conduit means connecting a second outlet port of the first fluid amplifier to a second control port of the second fluid amplifier; fifth conduit means connecting a first outlet port of the second fluid amplifier to the first chamber of the roll; and sixth conduit means connecting a second outlet port of the second fluid amplifier to the second chamber of the roll.

Claim 10

In an electrophotographic reproduction machine including a casing; a movable electrophotographic recording belt in said casing; a charging station mounted in said casing to provide a positive electrostatic charge on said belt; an imaging station mounted in said casing for illuminating a document to be reproduced onto said belt to provide a positively charged electrostatic latent image corresponding to the document on said belt; a development station mounted in said casing for rendering the electrostatic latent image on said belt visible by negatively charged toner attracted thereto; a transfer station mounted in said casing for transferring the toner image to a support medium; a cleaning station mounted in said casing for removing residual toner from said belt; and means for supporting the belt for movement in seriatum past the charging station, imaging station, development station, transfer station and cleaning station, the improvement comprising: said supporting means including a steering roll for inducing inward and outward edgewise travel of said web, said steering roll having an elastomeric material as its outer perimetric surface; partition means dividing the interior of the roll into first and second axially spaced chambers, and means responsive to inward and outward edgewise travel of said web from a predetermined alignment for applying fluid pressure to each of the first and second chambers to change the relative pressure between the chambers to produce relative expansion and contraction between the axial ends of said elastomeric material to effect back and forth tilting of the perimetric surface of the roll between oppositely inclined positions and thereby prOvide the inward and outward edgewise travel of said web to maintain the predetermined alignment.

Claim 11

In an electrophotographic reproduction machine including a casing; a movable electrophotographic recording belt in said casing; a charging station mounted in said casing to provide a positive electrostatic charge on said belt; an imaging station mounted in said casing for illuminating a document to be reproduced onto said belt to provide a positively charged electrostatic latent image corresponding to the document on said belt; a development station mounted in said casing for rendering the electrostatic latent image on said belt visible by negatively charged toner attracted thereto; a transfer station mounted in said casing for transferring the toner image to a support medium; a cleaning station mounted in said casing for removing residual toner from said belt; and means for supporting the belt for movement in seriatum past the charging station, imaging station, development station, transfer station and cleaning station, the improvement comprising: said supporting means including a steering roll for inducing inward and outward edgewise travel of said web, said steering roll having an elastomeric material as its outer perimetric surface; partition means dividing the interior of the roll into first and second axially spaced chambers, and means responsive to inward and outward edgewise travel of said web from a predetermined alignment for applying fluid pressure to each of the first and second chambers to change the relative pressure between the chambers to produce relative expansion and contraction between the axial ends of said elastomeric material to effect back and forth tilting of the perimetric surface of the roll between oppositely inclined positions and thereby prOvide the inward and outward edgewise travel of said web to maintain the predetermined alignment.

Claim 12

The electrophotographic reproduction machine as defined in claim 8 wherein said means for applying fluid pressure to each of the pair of chambers to change the relative pressure between the pair of chambers comprises: a sensing means including a receiver for receiving a stream of fluid and a nozzle aligned with the receiver for directing a stream of fluid toward said receiver, said nozzle and receiver being positioned at one edge of the web at opposite surfaces thereof for back and forth movement of said one edge of the web between the nozzle and the receiver to increase and decrease the fluid pressure received by said receiver from said nozzle in response to uncovering and covering, respectively, of said receiver; and control means responsive to increases and decreases in pressure in said receiver, said control means increasing the fluid pressure in the first chamber with respect to the second chamber to tilt the perimetric surface of the roll to one of said oppositely inclined positions which causes movement of the web in a direction to cover said receiver, said control means in response to a decrease in pressure in said receiver increasing the fluid pressure in the second chamber with respect to the first chamber to tilt the perimetric surface of the roll to the other of said oppositely inclined positions which causes movement of the web in a direction to uncover said receiver.

Claim 13

The electrophotographic reproduction machine as defined in claim 9 wherein the control means includes a source of air pressure, first conduit means connecting the source of air pressure to said nozzle; fluid amplification means; including first and second fluid amplifiers; first conduit means for connecting the source of air pressure to a supply port and a first control port of the first fluid amplifier and to a supply port of the second fluid amplifier; second conduit means connecting the receiver to a second control port of the first fluid amplifier; third conduit means connecting a first outlet port of the first fluid amplifier to a first control port of the second fluid amplifier; fourth conduit means connecting a second outlet port of the first fluid amplifier to a second control port of the second fluid amplifier; fifth conduit means connecting a first outlet port of the second fluid amplifier to the first chamber of the roll; and sixth conduit means connecting a second outlet port of the second fluid amplifier to the second chamber of the roll.