Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
158 words
A method for applying a negative pressure over a suction sector of an air-pervious mantle of a roll, comprising the steps of: providing a suction chamber within said pervious roll mantle to extend over said suction sector of said roll, said suction chamber having a pair of circumferentially spaced, axially extending outermost edge zones situated directly adjacent to and forming respective gaps with an inner surface of said pervious roll mantle, said outermost edge zones defining boundaries of said suction chamber; directing air jets away from said suction chamber at said outermost edge portions of said suction chamber through said gaps, said gaps being sufficiently small so that said air jets cause air currents to be ejected from said suction chamber at said outermost edge zones thereof; and said air currents producing non-contacting air seals at said gaps at said outermost edge zones of said suction chamber and, at least partly, a negative pressure in said suction chamber.
Claim 2
Independent Claim
158 words
A method for applying a negative pressure over a suction sector of an air-pervious mantle of a roll, comprising the steps of: providing a suction chamber within said pervious roll mantle to extend over said suction sector of said roll, said suction chamber having a pair of circumferentially spaced, axially extending outermost edge zones situated directly adjacent to and forming respective gaps with an inner surface of said pervious roll mantle, said outermost edge zones defining boundaries of said suction chamber; directing air jets away from said suction chamber at said outermost edge portions of said suction chamber through said gaps, said gaps being sufficiently small so that said air jets cause air currents to be ejected from said suction chamber at said outermost edge zones thereof; and said air currents producing non-contacting air seals at said gaps at said outermost edge zones of said suction chamber and, at least partly, a negative pressure in said suction chamber.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said negative pressure produced in said suction chamber is in the range of between about 50 to 300 Pa.
Claim 4
Dependent Claim
54 words
The method of claim 1 wherein said suction chamber has a pair of axial ends and further including sealing at least one of said axial ends of said suction chamber by directing air jets away from said suction chamber at said at least one axial end thereof, without the use of contact-type sealing elements.
Claim 5
Dependent Claim
48 words
The method of claim 1 wherein said suction chamber has a pair of axial ends and further including sealing at least one of said axial ends of said suction chamber by providing a sealing member which is spaced a small distance from said inner surface of said mantel.
Claim 6
Dependent Claim
15 words
The method of claim 4 wherein said small distance is less than about 2 mm.
Claim 7
Dependent Claim
33 words
The method of claim 1 wherein said air jets are directed through nozzle slots provided at said outermost edge portions of said suction chamber, said air jets being directed by the Coanda principle.
Claim 8
Dependent Claim
66 words
The method of claim 1 wherein said air jets are directed through blow nozzles provided at said outermost edge portions of said suction chamber, each of said blow nozzles including an outer wall forming said gap with said inner surface of said roll mantle, and wherein said air jets are directed substantially parallel to the tangent of said mantle at the region of said blow nozzles.
Claim 9
Dependent Claim
47 words
The method of claim 1 including the further step of communicating said suction chamber with a source of negative pressure so that the negative pressure produced by means of said ejected air currents is only a part of a total negative pressure produced in said suction chamber.
Claim 10
Dependent Claim
200 words
A suction roll, comprising: a cylindrical air-pervious mantle, said mantle having ends at which said mantle is mounted for rotation, said mantle defining an interior space therewithin; a suction chamber situated in said interior space, said suction chamber being defined by first axially extending wall means having outermost edge portions situated directly adjacent to an inner surface of said roll mantle forming respective gaps therewith defining boundaries of said suction chamber, said mantle having a suction sector defined between said boundaries; a pressure chamber situated in said interior space in communication with said suction chamber including means for connection to a pressure source; and blow nozzle means for directing air jets away from said suction chamber through said gaps, said blow nozzle means having inlet sides communicating with said pressure chamber, said gaps being sufficiently small so that said air jets cause air currents to be ejected from said suction chamber through said gaps at said outermost edge portions of said first wall means, said blow nozzle means structured so that said air currents produce non-contacting seals at said gaps at said outermost edge portions of said wall means and, at least partly, a negative pressure in said suction chamber.
Claim 11
Dependent Claim
200 words
A suction roll, comprising: a cylindrical air-pervious mantle, said mantle having ends at which said mantle is mounted for rotation, said mantle defining an interior space therewithin; a suction chamber situated in said interior space, said suction chamber being defined by first axially extending wall means having outermost edge portions situated directly adjacent to an inner surface of said roll mantle forming respective gaps therewith defining boundaries of said suction chamber, said mantle having a suction sector defined between said boundaries; a pressure chamber situated in said interior space in communication with said suction chamber including means for connection to a pressure source; and blow nozzle means for directing air jets away from said suction chamber through said gaps, said blow nozzle means having inlet sides communicating with said pressure chamber, said gaps being sufficiently small so that said air jets cause air currents to be ejected from said suction chamber through said gaps at said outermost edge portions of said first wall means, said blow nozzle means structured so that said air currents produce non-contacting seals at said gaps at said outermost edge portions of said wall means and, at least partly, a negative pressure in said suction chamber.
Claim 12
Dependent Claim
31 words
The suction roll of claim 11 wherein said blow nozzle means direct said air jets substantially parallel to the tangent of said mantle at the region of said blow nozzle means.
Claim 13
Dependent Claim
110 words
The suction roll of claim 9, wherein said suction chamber communicates with a suction sector of said pervious roll mantle and wherein said pressure chamber communicates with a pressure sector with said roll outside of said suction sector, and wherein said pressure chamber includes second axially extending wall means which also extend between said blow nozzle means, said second wall means and said pressure sector of said roll define said pressure chamber, said air jets directed through said blow nozzle means and said air currents ejected from said suction chamber being directed into said pressure chamber to create a discharge air flow through said pressure sector of said pervious mantle.
Claim 14
Dependent Claim
53 words
The suction roll of claim 11 further including a stationary air inlet pipe situated within said interior space defined within said roll mantle, said first and second wall means defining said suction and pressure chambers being attached to said air inlet pipe, said pipe being provided with openings communicating with said pressure chamber.
Claim 15
Dependent Claim
60 words
The suction roll of claim 9 wherein said suction chamber has a pair of axial ends, and further including end blow nozzle means situated at the axial ends of said suction chamber for directing air jets away from said suction sector so that the use of contact-type sealing elements can be eliminated at the axial ends of said suction chamber.
Claim 16
Dependent Claim
19 words
The suction roll of claim 9 wherein said blow nozzle means comprise nozzle slots operating by the Coanda principle.
Claim 17
Dependent Claim
34 words
The suction roll of claim 9 wherein each of said blow nozzle means comprise a series of openings provided in a wall situated substantially in a plane containing the axis of said suction roll.
Claim 18
Dependent Claim
27 words
The suction roll of claim 9 wherein said blow nozzle means each include an outer wall forming said gap with said inner surface of said roll mantel.
Claim 19
Dependent Claim
20 words
The suction roll of claim 16 wherein said gap is in the range of between about 3 to 30 mm.
Claim 20
Dependent Claim
20 words
The suction roll of claim 17 wherein said gap is in the range of between about 8 to 20 mm.
Claim 21
Dependent Claim
33 words
The suction roll of claim 9 wherein said blow nozzle means comprise nozzle slots and wherein the width of said nozzle slots is in the range of between about 0.5 to 5 mm.
Claim 22
Dependent Claim
24 words
The suction roll of claim 19 wherein the width of said nozzle slots is in the range of between about 2 to 3 mm.
Claim 23
Dependent Claim
204 words
Apparatus for handling web material, said apparatus including in combination therewith at least one suction roll, comprising: a suction roll including an air-pervious mantle having ends at which said mantle is mounted for rotation, said mantle defining an interior space therewithin; a suction chamber situated in said interior space, said suction chamber being defined by first axially extending wall means having outermost edge portions situated directly adjacent to an inner surface of said roll mantle and forming respective gaps therewith defining boundaries of said suction chamber, said mantle having a suction sector defined between said boundaries; a pressure chamber situated in said interior space in communication with said suction chamber including means for connection to a pressure source; and blow nozzle means for directing air jets away from said suction chamber through said gaps, said gaps being sufficiently small so that said air jets cause air currents to be ejected out from said suction chamber through said gaps at said outermost edge portions of said first wall means, said blow nozzle means structured so that said air currents produce non-contacting seals at said gaps at said outermost edge portions of said wall means and, at least partly, a negative pressure in said suction chamber.
Claim 24
Dependent Claim
204 words
Apparatus for handling web material, said apparatus including in combination therewith at least one suction roll, comprising: a suction roll including an air-pervious mantle having ends at which said mantle is mounted for rotation, said mantle defining an interior space therewithin; a suction chamber situated in said interior space, said suction chamber being defined by first axially extending wall means having outermost edge portions situated directly adjacent to an inner surface of said roll mantle and forming respective gaps therewith defining boundaries of said suction chamber, said mantle having a suction sector defined between said boundaries; a pressure chamber situated in said interior space in communication with said suction chamber including means for connection to a pressure source; and blow nozzle means for directing air jets away from said suction chamber through said gaps, said gaps being sufficiently small so that said air jets cause air currents to be ejected out from said suction chamber through said gaps at said outermost edge portions of said first wall means, said blow nozzle means structured so that said air currents produce non-contacting seals at said gaps at said outermost edge portions of said wall means and, at least partly, a negative pressure in said suction chamber.
Claim 25
Dependent Claim
94 words
The combination of claim 21 wherein said apparatus comprises a single-wire draw drying section of a paper machine including a group of drying cylinders including a line of drying cylinders, said at least one suction roll comprising an idler roll in said drying section, and a drying wire carrying said web into contact with said drying cylinders of said line with said drying wire being situated within said web and said suction sector of said suction roll whereby said suction sector maintains the web in contact with said drying wire over said suction roll.
Claim 26
Dependent Claim
104 words
The combination of claim 21 wherein said apparatus comprises a twin-wire draw drying section of a paper machine including upper and lower lines of drying cylinders, said at least one suction roll comprising an idler roll in said drying section, upper and lower drying wires carrying said web into contact with said drying cylinders of said upper and lower lines, transfer nips formed in connection with said idler rolls in which said web is transferred from one drying wire onto the other, and wherein the web is maintained in contact with a drying wire by means of said suction sector of said suction roll.
Claim 27
Dependent Claim
60 words
The combination of claim 21 wherein said apparatus comprises a cutting means for cutting said web into sheets, said at least one suction roll acting to shift said web or sheets cut therefrom forwardly and wherein said suction sector acts as a holding zone within which the web or sheets cut therefrom is held in contact with said suction roll.
Claim 28
Dependent Claim
83 words
The combination of claim 21 wherein said apparatus comprises a twin-wire draw drying section of a paper machine and wherein at least one suction roll comprises a combined felt guide roll and pocket ventilation roll, and wherein said suction sector comprises means for removing moist air from a pocket space of said drying section and wherein warm, dry air is used as blow air for said air jets, said warm, dry air being used in said pocket space as drying pocket ventilation air.