Abstract A portion of a papermaking machine is disclosed having several web-forming units in series for making heavy or multilayer paper. Each forming unit includes a headbox mounted above an impervious forming roll for discharging pulp into a nip between a pair of belts coming together and lapping a down turning side of the forming roll. Both belts may be wire fabrics or, preferably, one belt is a felt fabric making contact with the forming roll and the other belt is a wire and arranged radially outward of the felt. The pulp is formed into a web sandwiched between the radially inner felt and radially outer wire and water is squeezed from the pulp web outwardly through the wire. At the bottom of the forming roll the felt is located over the web and wire, and the felt-web-wire is removed from the forming roll and turned downwardly away from the forming roll and inverted to place the wire and web on top of the felt. The wire is lifted from the web and looped back to the forming roll while the web remains on top of the felt and is carried thereby through successive similar forming units for applying additional layers of pulp to the web.
Inventors
👤 Donald B De Noyer
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 12:05
CPC Classifications
D; D21; D21F; D21F11/00; D21F11/02; D21F11/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
156 words
An apparatus according to claim 1 in which each first guiding means comprises a first turning roll spaced above the forming roll of each unit; each second guiding means comprises a second turning roll arranged to press the first belt, the web and the second belt against a portion of the underside of the forming roll of each unit, and a third turning roll spaced below each second turning roll to direct the belts and web along a downward path from the second turning roll to the third turning roll; and each third guiding means comprises a fourth turning roll guiding the belts and web to turn around at least a portion of the underside of the third turning roll in each unit with centrifugal force thereby being imparted to supplement grAvitational force tending to accelerate water pressed out of the web as the belts and web turn on the third turning roll in each unit.
Claim 2
Dependent Claim
166 words
An apparatus according to claim 1 in which each first guiding means comprises a first turning roll spaced above the forming roll of each unit; each second guiding means comprises a second turning roll arranged to press the first belt, the web and the second belt against a portion of the underside of the forming roll of each unit, and a third turning roll spaced below each second turning roll to direct the belts and web along a downward path from the second turning roll to the third turning roll; and each third guiding means comprises a fourth turning roll spaced above the third turning roll in each unit, to direct the belts and web in each unit along an upwardly directed path from the third turning roll to the fourth turning roll with centrifugal force thereby being imparted to supplement gravitational force tending to accelerate water pressed out of the web as the belts and web turn on the third turning roll in each unit.
Claim 3
Dependent Claim
50 words
An apparatus according to claim 2 in which a save-all is arranged in each unit in the space above the third turning roll, between the second and fourth turning rolls, and below the forming roll to collect water pressed from the pulp as the belts turn on the forming roll.
Claim 4
Dependent Claim
44 words
An apparatus according to claim 1 in which a suction box is provided in each unit beneath the belts and web between the second and third guiding means, and with at least a portion of the suction box extending beneath the third guiding means.
Claim 5
Dependent Claim
44 words
An apparatus according to claim 2 in which a suction box is provided in each unit beneath the belts and web between the third and fourth turning rolls, and with at least a portion of the suction box extending beneath the fourth turning roll.